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Names of large numbers

Adapted from Wikipedia · Discoverer experience

An old manuscript page showing an early description of large numbers.

Large numbers help us talk about huge amounts without writing long strings of digits. For example, instead of writing 10,000,000, we can say "ten million." Different places and languages have their own ways of naming these big numbers, which can sometimes cause confusion.

Two main systems are used in the world: the short scale and the long scale. In the short scale, used in most English-speaking countries, each new name for a large number adds a thousand times more than the last. The long scale, used in many parts of Europe and South America, adds a million times more. This means that the same name, like "billion," can mean different amounts depending on which system is used.

Some large numbers, like "lakh" and "crore," are special to certain regions. In the Indian numbering system, a lakh is 100,000, and a crore is 10,000,000. These names make talking about big amounts easier in everyday life.

Even though we often use scientific notation in science, knowing the names of large numbers can be fun and useful. It helps us understand statements like "There are about seven octillion atoms in the human body," even if we don’t use such big numbers every day.

Informal words like "zillion" are sometimes used to mean any very large amount, even if it isn’t a real number. These fun terms add color to how we talk about huge quantities.

Standard dictionary numbers

Different places use different systems to name very large numbers. For example, US, English Canada, modern British, Australia, and Eastern Europe use what is called the short scale. On the other hand, French Canada, older British, Western Europe, and Central Europe use the long scale.

Most of these large numbers end in -illion, like million. Words like centillion are among the highest names ending in -illion found in dictionaries. Some people talk about even bigger numbers like trigintillion, but these are not usually listed in standard dictionaries. Two special numbers, googol and googolplex, are included in dictionaries. They were first mentioned in a book by Kasner and Newman. However, these are not used in formal math.

xName
(SS/LS, LS)
SS
(103x+3)
LS
(106x, 106x+3)
Appearance in different dictionaries
AHD4CEDCODMWOEDRHD2SOED3W3HM
1million106106
milliard109
2billion1091012
3trillion10121018
4quadrillion10151024
5quintillion10181030
6sextillion10211036
7septillion10241042
8octillion10271048
9nonillion10301054
10decillion10331060
11undecillion10361066
12duodecillion10391072
13tredecillion10421078
14quattuordecillion10451084
15quindecillion10481090
16sexdecillion10511096
17septendecillion105410102
18octodecillion105710108
19novemdecillion106010114
20vigintillion106310120
100centillion1030310600
NameValueAuthorities
AHD4CEDCODMWOEDRHD2SOED3W3HM
googol10100
googolplex10googol (1010100)

Usage of names of large numbers

Some large numbers, like million, billion, and trillion, are used often in everyday life, especially in topics like money and economics. For example, during times of hyperinflation, countries have needed to use very large numbers to describe their money.

However, very large numbers like sextillion are rarely used outside of special lists or discussions. In science, these huge numbers are usually written using scientific notation, like "1045", instead of their name. One early example of naming large numbers is found in The Sand Reckoner by Archimedes, where he created a system to name extremely large numbers and even estimated how many grains of sand it would take to fill the entire universe.

Origins of the "standard dictionary numbers"

The words bymillion and trimillion were first recorded in 1475 in a manuscript by Jehan Adam. Later, Nicolas Chuquet wrote a book called Triparty en la science des nombres, which was not published during his lifetime but was partly copied by Estienne de La Roche in his 1520 book L'arismetique.

Chuquet described large numbers in groups of six digits. He used names like byllion for 1012 and tryllion for 1018. These early writers used what is called the long scale to name very large numbers.

Googol family

The words googol and googolplex were created by a young boy, the nephew of mathematician Edward Kasner. They appeared in the 1940 book Mathematics and the Imagination. A googol is the number 1 followed by one hundred zeros, and a googolplex is an even larger number — 1 followed by a googol zeros.

These fun names inspired the big tech company Google and its headquarters, called the Googleplex. Some mathematicians have suggested other names for huge numbers, like googolplexplex for a number that's 10 raised to the power of a googolplex, but these aren't used very often.

ValueNameAuthority
10100googolKasner and Newman, dictionaries (see above)
10googol = 1010100googolplexKasner and Newman, dictionaries (see above)

Extensions of the standard dictionary numbers

Further information: billion and Long and short scales

Different cultures and languages have their own ways of naming very large numbers. In traditional British usage, each new name was given for every power of one million. For example, 1,000,000 is called one million, and 1,000,000 squared (1,000,0002) is called one billion.

In traditional American, Canadian, and modern British usage, new names are given for each power of one thousand. Here, a billion means 1000 × 10002, which equals 109. This system is widely used in finance and international documents, like those from the United Nations.

The way these names are created involves using Latin roots and adding the suffix "-illion". For example, by combining roots for numbers, we can name numbers as large as 103000 or even bigger!

UnitsTensHundreds
0
1UnNDeciNXCenti
2DuoMSVigintiNDucenti
3TreSNSTrigintaNSTrecenti
4QuattuorNSQuadragintaNSQuadringenti
5Quinqua3NSQuinquagintaNSQuingenti
6SeSXNSexagintaNSescenti
7SepteMNNSeptuagintaNSeptingenti
8OctoMXOctogintaMXOctingenti
9NoveMNNonagintaNongenti
Base -illion
(short scale)
Base -illion
(long scale)
ValueUS, Canada, and modern British
(short scale)
Traditional British
(long scale)
Traditional European
(Peletier long scale)
11106millionmillionmillion
21109billionthousand millionmilliard
321012trillionbillionbillion
421015quadrillionthousand billionbilliard
531018quintilliontrilliontrillion
631021sextillionthousand trilliontrilliard
741024septillionquadrillionquadrillion
841027octillionthousand quadrillionquadrilliard
951030nonillionquintillionquintillion
1051033decillionthousand quintillionquintilliard
1161036undecillionsextillionsextillion
1261039duodecillionthousand sextillionsextilliard
1371042tredecillionseptillionseptillion
1471045quattuordecillionthousand septillionseptilliard
1581048quindecillionoctillionoctillion
1681051sedecillionthousand octillionoctilliard
1791054septendecillionnonillionnonillion
1891057octodecillionthousand nonillionnonilliard
19101060novendecilliondecilliondecillion
20101063vigintillionthousand decilliondecilliard
21111066unvigintillionundecillionundecillion
22111069duovigintillionthousand undecillionundecilliard
23121072tresvigintillionduodecillionduodecillion
24121075quattuor­vigint­illionthousand duodecillionduodecilliard
25131078quinvigintilliontredecilliontredecillion
26131081sesvigintillionthousand tredecilliontredecilliard
27141084septemvigintillionquattuordecillionquattuordecillion
28141087octovigintillionthousand quattuordecillionquattuordecilliard
29151090novemvigintillionquindecillionquindecillion
30151093trigintillionthousand quindecillionquindecilliard
31161096untrigintillionsedecillionsedecillion
32161099duotrigintillionthousand sedecillionsedecilliard
331710102trestrigintillionseptendecillionseptendecillion
341710105quattuor­trigint­illionthousand septendecillionseptendecilliard
351810108quintrigintillionoctodecillionoctodecillion
361810111sestrigintillionthousand octodecillionoctodecilliard
371910114septentrigintillionnovendecillionnovendecillion
381910117octotrigintillionthousand novendecillionnovendecilliard
392010120noventrigintillionvigintillionvigintillion
402010123quadragintillionthousand vigintillionvigintilliard
502510153quinquagintillionthousand quinvigintillionquinvigintilliard
603010183sexagintillionthousand trigintilliontrigintilliard
703510213septuagintillionthousand quintrigintillionquintrigintilliard
804010243octogintillionthousand quadragintillionquadragintilliard
904510273nonagintillionthousand quin­quadra­gint­illionquin­quadra­gint­illiard
1005010303centillionthousand quinquagintillionquinquagintilliard
1015110306uncentillionunquinquagintillionunquinquagintillion
1105510333decicentillionthousand quin­quinqua­gint­illionquin­quinqua­gint­illiard
1115610336undecicentillionses­quinqua­gint­illionses­quinqua­gint­illion
1206010363viginticentillionthousand sexagintillionsexagintilliard
1216110366unviginticentillionunsexagintillionunsexagintillion
1306510393trigintacentillionthousand quinsexagintillionquinsexagintilliard
1407010423quadra­gintacent­illionthousand septuagintillionseptuagintilliard
1507510453quinqua­gintacent­illionthousand quin­septua­gint­illionquin­septua­gint­illiard
1608010483sexagintacentillionthousand octogintillionoctogintilliard
1708510513septuagintacentillionthousand quinoctogintillionquinoctogintilliard
1809010543octogintacentillionthousand nonagintillionnonagintilliard
1909510573nonagintacentillionthousand quinnonagintillionquinnonagintilliard
20010010603ducentillionthousand centillioncentilliard
30015010903trecentillionthousand quinqua­gintacent­illionquinqua­gintacent­illiard
400200101203quadringentillionthousand ducentillionducentilliard
500250101503quingentillionthousand quinqua­gintaducent­illionquinqua­gintaducent­illiard
600300101803sescentillionthousand trecentilliontrecentilliard
700350102103septingentillionthousand quinqua­gintatrecent­illionquinqua­gintatrecent­illiard
800400102403octingentillionthousand quadringentillionquadringentilliard
900450102703nongentillionthousand quinqua­ginta­quadringent­illionquinqua­ginta­quadringent­illiard
1000500103003millinillionthousand quingentillionquingentilliard

Unit prefixes

Main articles: Metric prefix and Binary prefix

Unit prefixes are special names used to describe very large or very small numbers. They help us talk about quantities like a thousand or a million in a shorter way. For example, instead of saying "one billion bytes," we can say "one gigabyte." These prefixes are used with two common systems: one for powers of 1000 and another for powers of 1024.

DecimalBinary
ValueSIValueIEC
1000 (103)kkilo1024 (210)Kikibi
10002 (106)Mmega10242 (220)Mimebi
10003 (109)Ggiga10243 (230)Gigibi
10004 (1012)Ttera10244 (240)Titebi
10005 (1015)Ppeta10245 (250)Pipebi
10006 (1018)Eexa10246 (260)Eiexbi
10007 (1021)Zzetta10247 (270)Zizebi
10008 (1024)Yyotta10248 (280)Yiyobi
10009 (1027)Rronna10249 (290)Rirobi
100010 (1030)Qquetta102410 (2100)Qiquebi

Other named large numbers used in mathematics, physics and chemistry

Some very large numbers have special names used in science and math. For example, the Avogadro number tells us how many tiny particles are in one mole, a unit used in chemistry. Other big numbers like the Eddington number, which estimates the number of protons in the whole universe, or Graham's number, which comes from a complex math problem, help scientists talk about incredibly large amounts in a shorter way than using all the digits.

Related articles

This article is a child-friendly adaptation of the Wikipedia article on Names of large numbers, available under CC BY-SA 4.0.

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