What is a composite number? Definition, examples.

Composite numbers definition

  • A composite number is a positive integer that has at least one positive divisor other than 1 and the number itself.
  • Positive integers larger than 1 that are only dividing by themselves and 1 are called prime numbers.
    A composite number is also any positive integer larger than 1 that is not a prime number.

Examples of composite numbers. Examples of numbers that are not composite, but prime.

All the composite numbers, up to 100:

There is no known simple formula that sets all of the prime numbers apart from composites.


What is a prime number?

What is a composite number?

Prime numbers up to 1,000

Prime numbers up to 10,000

Sieve of Eratosthenes

Euclid's algorithm

Simplifying ordinary (common) math fractions (reducing to lower terms): steps to follow and examples