Composite number

Definition: A composite number is an integer than is composed of integer factors. It is the opposite of a prime number.
A composite number is one that can be formed by multiplying some integers* together. For example 18 is composite because
18 = 2 × 3 × 3
It follows that composite numbers are never prime numbers. For more see Prime numbers.
* The integers must be greater than one.
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Other number topics

Scalar numbers

Counting numbers

Numbers that have factors

Special values