The Number

21990

Twenty-One Thousand Nine Hundred and Ninety

In Base 15 Quindecimal Is

67b015

The numbers with a 15 subscript use Base 15 Quindecimal 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
67ac15
Twenty-One Thousand Nine Hundred and Eighty-Seven in Base 15 Quindecimal
21988
67ad15
Twenty-One Thousand Nine Hundred and Eighty-Eight in Base 15 Quindecimal
21989
67ae15
Twenty-One Thousand Nine Hundred and Eighty-Nine in Base 15 Quindecimal
21991
67b115
Twenty-One Thousand Nine Hundred and Ninety-One in Base 15 Quindecimal
21992
67b215
Twenty-One Thousand Nine Hundred and Ninety-Two in Base 15 Quindecimal
21993
67b315
Twenty-One Thousand Nine Hundred and Ninety-Three in Base 15 Quindecimal

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.

0.000247ed0111ae10815

The reciprocal of 21990 in Base 15 Quindecimal.

Palindrome?

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

The number 67b015 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 15 Quindecimal

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
215
Two in Base 15 Quindecimal
3
315
Three in Base 15 Quindecimal
5
515
Five in Base 15 Quindecimal
733
33d15
Seven Hundred and Thirty-Three in Base 15 Quindecimal

Prime Factorization

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

2151 · 3151 · 5151 · 33d151 = 67b015

Base Conversions

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