What are the Factors of 28?

The following are the different types of factors of 28:

• Factors of 28: 1, 2, 4, 7, 14, 28

• Sum of Factors of 28: 56

• Negative Factors of 28: -1, -2, -4, -7, -14, -28

• Prime Factors of 28: 2, 7

• Prime Factorization of 28: 2^2 × 7^1

There are two ways to find the factors of 28: using factor pairs, and using prime factorization.

Factor pairs of 28 are any two numbers that, when multiplied together, equal 28. The question to ask is “what two numbers multiplied together equal 28?” Every factor can be paired with another factor, and multiplying the two will result in 28.

To find the factor pairs of 28, follow these steps:

Step 1:

Find the smallest prime number that is larger than 1, and is a factor of 28. For reference, the first prime numbers to check are 2, 3, 5, 7, 11, and 13. In this case, the smallest factor that’s a prime number larger than 1 is 2.

Step 2:

Divide 28 by the smallest prime factor, in this case, 2:

28 ÷ 2 = 14

2 and 14 will make a new factor pair.

Step 3:

Repeat Steps 1 and 2, using 14 as the new focus. Find the smallest prime factor that isn’t 1, and divide 14 by that number. In this case, 2 is the new smallest prime factor:

14 ÷ 2 = 7

Remember that this new factor pair is only for the factors of 14, not 28. So, to finish the factor pair for 28, you’d multiply 2 and 2 before pairing with 7:

2 x 2 = 4

Step 4:

Repeat this process until there are no longer any prime factors larger than one to divide by. At the end, you should have the full list of factor pairs.

Here are all the factor pairs for 28:

(1, 28), (2, 14), (4, 7)

So, to list all the factors of 28: 1, 2, 4, 7, 14, 28

The negative factors of 28 would be: -1, -2, -4, -7, -14, -28

To find the Prime factorization of 28, we break down all the factors of 28 until we are left with only prime factors. We then express n as a product of multiplying the prime factors together.

The process of finding the prime factorization of 28 only has a few differences from the above method of finding the factors of 28. Instead of ensuring we find the right factor pairs, we continue to factor each step until we are left with only the list of smallest prime factors greater than 1.

Here are the steps for finding the prime factorization of 28:

Step 1:

Find the smallest prime number that is larger than 1, and is a factor of 28. For reference, the first prime numbers to check are 2, 3, 5, 7, 11, and 13. In this case, the smallest factor that’s a prime number larger than 1 is 2.

Step 2:

Divide 28 by the smallest prime factor, in this case, 2

28 ÷ 2 = 14

2 becomes the first number in our prime factorization.

Step 3:

Repeat Steps 1 and 2, using 14 as the new focus. Find the smallest prime factor that isn’t 1, and divide 14 by that number. The smallest prime factor you pick for 14 will then be the next prime factor. If you keep repeating this process, there will be a point where there will be no more prime factors left, which leaves you with the prime factors for prime factorization.

So, the unique prime factors of 28 are: 2, 7

Practice your factoring skills by exploring how to factor other numbers, like the ones below:

Factors of 110 - The factors of 110 are 1, 2, 5, 10, 11, 22, 55, 110

Factors of 125 - The factors of 125 are 1, 5, 25, 125

Factors of 39 - The factors of 39 are 1, 3, 13, 39

Factors of 46 - The factors of 46 are 1, 2, 23, 46