Q: What are the prime factors of the number 243?

 A: 3

Why are those the prime factors of the number 243?

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 243

243
Factor Arrows
381
Factor Arrows
327
Factor Arrows
39
Factor Arrows
33

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

We can check our work by multiplying all of the prime factors together: 3 x 3 x 3 x 3 x 3 = 243

This can also be written as 35 = 243

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 243:


Ask a Question