Factors

The following set of definitions comes from Discrete Mathematics with Applications by Epp S. (second edition)  p. 132

If n and d are integers and d  <> 0, then

n is divisible by d, if and only if, n = d * k for some integer k.

Alternatively, we can say that

    n is a multiple of d, or

    d is a factor of n, or

    d is a divisor of n, or

    d divides n.