What is the GCF of 133 and 128?

Solution: The GCF of 133 and 128 is 1

Methods

How to find the GCF of 133 and 128 using Prime Factorization

One way to find the GCF of 133 and 128 is to compare the prime factorization of each number. To find the prime factorization, you can follow the instructions for each number here:

Here is the prime factorization of 133:

7^1 × 19^1

And this is the prime factorization of 128:

2^7

When you compare the prime factorization of these two numbers, you can see that there are no matching prime factors. When this is the case, it means that there are no common factors between these two numbers. As a result, the GCF of 133 and 128 is 1.

Thus, the GCF of 133 and 128 is: 1

How to Find the GCF of 133 and 128 by Listing All Common Factors

The first step to this method of finding the Greatest Common Factor of 133 and 128 is to find and list all the factors of each number. Again, you can see how this is done by looking at the “Factors of” articles that are linked to above.

Let’s take a look at the factors for each of these numbers, 133 and 128:

Factors of 133: 1, 7, 19, 133

Factors of 128: 1, 2, 4, 8, 16, 32, 64, 128

When you compare the two lists of factors, you can see that the only common factor is 1. So, in this case, the GCF of 133 and 128 is 1.

Find the GCF of Other Number Pairs

Want more practice? Try some of these other GCF problems:

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