We can use our divisibility rules to help us in our prime factorization.

For example...

Let's write 4, 680 in prime factorization.

Using our divisibility rules we know 10 is a factor.  The other factor would be 468.   10 can be
divided by 5 and 2. 

We know 468 is divisible by 9 because the sum of the digits is divisible by 9.  Here is a table to show the factorization...

   The prime factorization, found by using
divisibility rules is 2 ∙ 2  ∙ 3 ∙ 3 ∙ 3 ∙ 3 ∙ 3 ∙ 5 ∙ 5.

Let's Practice!