The Number

18

Eightteen

In Base 21 Unovigesimal Is

i21

The numbers with a 21 subscript use Base 21 Unovigesimal notation.

For more familiar numbers: See Eightteen in Base 10 Decimal

Nearby Numbers

Positive, nonzero integers within three units

15
f21
Fifteen in Base 21 Unovigesimal
16
g21
Sixteen in Base 21 Unovigesimal
17
h21
Seventeen in Base 21 Unovigesimal
19
j21
Nineteen in Base 21 Unovigesimal
20
k21
Twenty in Base 21 Unovigesimal
21
1021
Twenty-One in Base 21 Unovigesimal

Scientific Notation

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

1.8e1

Reciprocal

A number multiplied with its reciprocal is one.

0.13aaaaaaaaaa921

The reciprocal of 18 in Base 21 Unovigesimal.

Palindrome?

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

The number i21 is a palindrome.

Not A Prime Number

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

Eightteen is a composite number with 6 total factors (including 1 and itself).   See primes in Base 21 Unovigesimal

A Composite

Composites have more than just these two factors.

Eightteen is a composite number with 6 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 eightteen has the following 2 prime factors:

2
221
Two in Base 21 Unovigesimal
3
321
Three in Base 21 Unovigesimal

Prime Factorization

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

2211 · 3212 = i21

Base Conversions

The number eightteen in 35 different bases