Prime numbers
factor
a factor.
A factor
They are called relative prime numbers.
Like 21? Prime numbers.
Prime numbers have those factors.
Those are called prime numbers.
One of the numbers is a factor of the other.
Those numbers are called factors. A pair of those is called a factor pair.
To distinguish them from prime numbers. Composite means "made up of various parts or elements." Prime numbers have one and only one factor pair. Composite numbers have a various number of factor pairs, but always more than one.
A number with more than one factor is normal, since all numbers except 0 and 1 have more than one factor. A number with more than two factors is composite.
When one of the numbers is a factor of the other.