What are the Factors of 91?

The following are the different types of factors of 91:

• Factors of 91: 1, 7, 13, 91

• Sum of Factors of 91: 112

• Negative Factors of 91: -1, -7, -13, -91

• Prime Factors of 91: 7, 13

• Prime Factorization of 91: 7^1 × 13^1

There are two ways to find the factors of 91: using factor pairs, and using prime factorization.

Factor pairs of 91 are any two numbers that, when multiplied together, equal 91. The question to ask is “what two numbers multiplied together equal 91?” Every factor can be paired with another factor, and multiplying the two will result in 91.

To find the factor pairs of 91, follow these steps:

Step 1:

Find the smallest prime number that is larger than 1, and is a factor of 91. 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 7.

Step 2:

Divide 91 by the smallest prime factor, in this case, 7:

91 ÷ 7 = 13

7 and 13 will make a new factor pair.

Step 3:

Repeat Steps 1 and 2, using 13 as the new focus. Find the smallest prime factor that isn’t 1, and divide 13 by that number. In this case, 13 is the new smallest prime factor:

13 ÷ 13 = 1

Remember that this new factor pair is only for the factors of 13, not 91. So, to finish the factor pair for 91, you’d multiply 7 and 13 before pairing with 1:

7 x 13 = 91

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 91:

(1, 91), (7, 13)

So, to list all the factors of 91: 1, 7, 13, 91

The negative factors of 91 would be: -1, -7, -13, -91

To find the Prime factorization of 91, we break down all the factors of 91 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 91 only has a few differences from the above method of finding the factors of 91. 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 91:

Step 1:

Find the smallest prime number that is larger than 1, and is a factor of 91. 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 7.

Step 2:

Divide 91 by the smallest prime factor, in this case, 7

91 ÷ 7 = 13

7 becomes the first number in our prime factorization.

Step 3:

Repeat Steps 1 and 2, using 13 as the new focus. Find the smallest prime factor that isn’t 1, and divide 13 by that number. The smallest prime factor you pick for 13 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 91 are: 7, 13

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

Factors of 100 - The factors of 100 are 1, 2, 4, 5, 10, 20, 25, 50, 100

Factors of 128 - The factors of 128 are 1, 2, 4, 8, 16, 32, 64, 128

Factors of 29 - The factors of 29 are 1, 29

Factors of 73 - The factors of 73 are 1, 73