Q: What are the prime factors of the number 21,309,399?

 A: 3, 29231

Why are those the prime factors of the number 21,309,399?

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 21,309,399

21,309,399
Factor Arrows
37,103,133
Factor Arrows
32,367,711
Factor Arrows
3789,237
Factor Arrows
3263,079
Factor Arrows
387,693
Factor Arrows
329,231

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:

3, 29231

We can check our work by multiplying all of the prime factors together: 3 x 3 x 3 x 3 x 3 x 3 x 29,231 = 21,309,399

This can also be written as 36 x 29,2311 = 21,309,399

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

Explore more about the number 21,309,399:


Ask a Question