# Names for large numbers facts for kids

Kids Encyclopedia Facts
(Redirected from Undecillion)

Naming very large numbers is relatively easy. There are two main ways of naming a number: scientific notation and naming by grouping. For example, the number 500 000 000 000 000 000 000 can be called 5 x 1020 in scientific notation since there are 20 zeros behind the 5. If the number is named by grouping, it is five hundred quintillion (American) or 500 trillion (European).

When large numbers have many different decimals in them, such as 642 500 000 000, naming them with scientific notation is about the same, but with one difference. Still counting the number of numbers after the first number (in this case, after the 6 there are 11 numbers) you need to include the ones that are not zero in the formula, but after a decimal point. So 642 500 000 000 will be 6.425 x 1011. When naming by grouping, each group of thrthe name of the group. With the same number, it would be said to be 642 billion, 500 million (US) or 642 milliard, 500 million (Eur).

## Some examples

Number Scientific notation Grouping
600 000 000 000 000 000 000 000 000 6 x 1026 600 septillion (quadrillion)
765 476 250 000 000 7.6547625 x 1014 765 trillion, 476 billion, 250 million
145 000 1.45 x 105 145 thousand

## Forms of numbering

The American way or "Short form" for naming large numbers is different from the European way or "Long form" of naming large numbers. This is mainly because of American finance. Short form numbering is based on thousands and Long form is based on millions. Because of this, in Short form a billion is one thousand millions (109) while in Long form it is one million millions (1012). The change in the United Kingdom to Short form numbering happened in 1974. Today, Short form is most commonly used in most English speaking countries.

## Names for large numbers

Scientific
notation
American name European name
100 One One
101 Ten Ten
102 Hundred Hundred
103 Thousand Thousand
104 Ten Thousand Ten Thousand
105 Hundred Thousand Hundred Thousand
106 Million Million
109 Billion Milliard
1012 Trillion Billion
1018 Quintillion Trillion
1021 Sextillion Trilliard
1030 Nonillion Quintillion
1033 Decillion Quintilliard
1036 Undecillion Sextillion
1039 Duodecillion Sextilliard
1042 Tredecillion Septillion
1045 Quattuordecillion Septilliard
1048 Quindecillion Octillion
1051 Sexdecillion Octilliard
1054 Septdecillion Nonillion
1057 Octodecillion Nonilliard
1060 Novemdecillion Decillion
1063 Vigintillion Decilliard

There is also the number googol, which is a 1 with 100 zeros behind it, and the number googolplex, which is a 1 with a googol of zeros behind it.

## Related pages

Names for large numbers Facts for Kids. Kiddle Encyclopedia.