Number 18 - properties and curiosities

18 (number)

18

Number 18 properties

  • Harshad
  • 18 is an even number.
  • 18 is a Harshad number, which means it is divisible by the sum of its digits (18 = 9, and 18 is divisible by 9).

Prime factorization

Prime factorization of 18: 2 × 3^2.

Divisors

Divisor count: 6

1, 2, 3, 6, 9, 18

Factors of 18 are: 1, 2, 3, 6, 9, 18.

Representations

In octal, 18 is represented as 22.

In binary, 18 is represented as 10010.

In hex, 18 is represented as 12.

Roman numeral: XVIII

Curiosities

  • 18 is divisible by the sum of its digits.

Quick answers

Is 18 prime?
No, 18 is not prime.

What are the factors of 18?
1, 2, 3, 6, 9, 18

What is 18 in binary?
10010