Respuesta :

A product of prime factors: multiplied only, and only, by prime factors, such as:

2, 3, 5, 7, 11, etc.

63 = 3 x 21
3 x 21 = 3 x 3 x 7

Let's check:

3 is a prime.
7 is a prime.

Correct!

[tex] 3^{2} *7 = 63[/tex].