Is 18 a composite or prime number

If a number is prime, that means no number will divide into it except itself and one. Let's try dividing 18 by some different numbers and seeing what we come up with.

18 / 7 = 2.57

18 / 4 = 4.5

18 / 17 = 1.06

18 / 2 = 9; this means 2 divides into 18.

And there you have it! 18 is not prime.

Let's examine it and find out:

The rule is: If a number has any other factors

besides '1' and itself, then it's composite.

The factors of 18 are: 1, 2, 3, 6, 9, and 18.

18 appears to be a composite number.