Q: What are the prime factors of the number 815?

Why are those the prime factors of the number 815?

Prime factors are the prime numbers that can be multipled together to equal the original number. You find the factors by dividing by prime numbers. It is best shown by creating a Factor Tree.

Factor Tree for the number 815

	815
5		163

The numbers in bold above are the prime factors. If there are multiples, you only count them one time. This leads us to our prime factors of:

5, 163

We can check our work by multiplying all of the prime factors together: 5 x 163 = 815

This can also be written as 5¹ x 163¹ = 815

If you would like to know more, or need additional explanation, please review our prime factorization explanation.

More Examples

Here are some more numbers to try:

Try the factor calculator