The Number

21

Twenty-One

In Base 31 Untrigesimal Is

l31

The numbers with a 31 subscript use Base 31 Untrigesimal notation.

For more familiar numbers: See Twenty-One in Base 10 Decimal

Nearby Numbers

Positive, nonzero integers within three units

18
i31
Eightteen in Base 31 Untrigesimal
19
j31
Nineteen in Base 31 Untrigesimal
20
k31
Twenty in Base 31 Untrigesimal
22
m31
Twenty-Two in Base 31 Untrigesimal
23
n31
Twenty-Three in Base 31 Untrigesimal
24
o31
Twenty-Four in Base 31 Untrigesimal

Scientific Notation

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

2.1e1

Reciprocal

A number multiplied with its reciprocal is one.

0.1enj5s1enj5o31

The reciprocal of 21 in Base 31 Untrigesimal.

Palindrome?

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

The number l31 is a palindrome.

Not A Prime Number

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

Twenty-one is a composite number with 4 total factors (including 1 and itself).   See primes in Base 31 Untrigesimal

A Composite

Composites have more than just these two factors.

Twenty-one is a composite number with 4 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 has the following 2 prime factors:

3
331
Three in Base 31 Untrigesimal
7
731
Seven in Base 31 Untrigesimal

Prime Factorization

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

3311 · 7311 = l31

Base Conversions

The number twenty-one in 35 different bases