Question

What is a composite number ?

Answer 1

A composite number is a positive integer that has a factor other than 1 and itself.

Example: 9 can be divided exactly by 3 (as well as 1 and 9), so 9 is a composite number.

But 7 cannot be divided exactly (except by 1 and 7), so 7 is not a composite number (it is a prime number).

All whole numbers above 1 are either composite or prime.