Q: What are the prime factors of the number 22,077,440?

A: 2, 5, 7, 11

Why are those the prime factors of the number 22,077,440?

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 22,077,440

	22,077,440

2		11,038,720

	2		5,519,360

		2		2,759,680

			2		1,379,840

				2		689,920

					2		344,960

						2		172,480

							2		86,240

								2		43,120

									2		21,560

										2		10,780

											2		5,390

												2		2,695

													5		539

														7		77

															7		11

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, 7, 11

We can check our work by multiplying all of the prime factors together: 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 x 5 x 7 x 7 x 11 = 22,077,440

This can also be written as 2¹³ x 5¹ x 7² x 11¹ = 22,077,440

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