- 1). Divide the large integer by 10 if it ends in 0 or by 5 if it ends in 5. Write the 10 or 5 and the answer to the division as your first two factors. For instance, 460 would become 46 x 10. If it does not end in 5 or 10, skip to Step 2.
- 2). Divide the integer by 2 if it is an even number. Then, write down both 2 and the answer to the division problem as your first two factors. If the number is not even, go to Step 3.
- 3). Divide the integer by 3 if the sum of its digits are divisible by 3. For example, you would divide the number 588 by 3 because 5 + 8 + 8 = 21, which is divisible by 3. Likewise, if the digits of the integer add up to make a number divisible by 9, divide the integer by 9.
- 4). Repeat the first three steps on the larger of your two factors to continue breaking it down. Circle the smaller factor if it is 2, 3 or 5, because it will be one of your final factors. If you were able to divide a 10 or 9 out, factor the 10 into 2 x 5 or the 9 into 3 x 3 and circle these.
- 5). Repeat Steps 1 through 4 on each new, larger factor until you have nothing but circled factors. Write down all of the circled factors in a row with multiplication signs in between them.