The Number

21990

Twenty-One Thousand Nine Hundred and Ninety

In Base 11 Undecimal Is

1558111

The numbers with a 11 subscript use Base 11 Undecimal notation.

For more familiar numbers: See Twenty-One Thousand Nine Hundred and Ninety in Base 10 Decimal

Nearby Numbers

Positive, nonzero integers within three units

21987
1557911
Twenty-One Thousand Nine Hundred and Eighty-Seven in Base 11 Undecimal
21988
1557a11
Twenty-One Thousand Nine Hundred and Eighty-Eight in Base 11 Undecimal
21989
1558011
Twenty-One Thousand Nine Hundred and Eighty-Nine in Base 11 Undecimal
21991
1558211
Twenty-One Thousand Nine Hundred and Ninety-One in Base 11 Undecimal
21992
1558311
Twenty-One Thousand Nine Hundred and Ninety-Two in Base 11 Undecimal
21993
1558411
Twenty-One Thousand Nine Hundred and Ninety-Three in Base 11 Undecimal

Scientific Notation

Scientific notation expresses a quantity as the product of its significand with 10 raised to an integer exponent.

2.1990e4

Reciprocal

A number multiplied with its reciprocal is one.

0.0000736201a939a1a2111

The reciprocal of 21990 in Base 11 Undecimal.

Palindrome?

A numerical palindrome has the same value when all of its digits are reversed.

The number 1558111 is not a palindrome.

Not A Prime Number

A prime number is a positive integer that is divisible only by itself and one.

Twenty-one thousand nine hundred and ninety is a composite number with 16 total factors (including 1 and itself).   See primes in Base 11 Undecimal

A Composite

Composites have more than just these two factors.

Twenty-one thousand nine hundred and ninety is a composite number with 16 total factors (including 1 and itself).

Prime Factors

The prime factors of a positive integer are the integers that divide it exactly and are also prime.

The number twenty-one thousand nine hundred and ninety has the following 4 prime factors:

2
211
Two in Base 11 Undecimal
3
311
Three in Base 11 Undecimal
5
511
Five in Base 11 Undecimal
733
60711
Seven Hundred and Thirty-Three in Base 11 Undecimal

Prime Factorization

The prime factorization of a positive integer is the unique list of prime factors together with their multiplicities

2111 · 3111 · 5111 · 607111 = 1558111

Base Conversions

The number twenty-one thousand nine hundred and ninety in 35 different bases