Q: What are the prime factors of the number 21,141,640?

 A: 2, 5, 13, 109, 373

Why are those the prime factors of the number 21,141,640?

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 21,141,640

21,141,640
Factor Arrows
210,570,820
Factor Arrows
25,285,410
Factor Arrows
22,642,705
Factor Arrows
5528,541
Factor Arrows
1340,657
Factor Arrows
109373

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:

2, 5, 13, 109, 373

We can check our work by multiplying all of the prime factors together: 2 x 2 x 2 x 5 x 13 x 109 x 373 = 21,141,640

This can also be written as 23 x 51 x 131 x 1091 x 3731 = 21,141,640

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 21,141,640:


Ask a Question