What two numbers have a GCF of 640?

Here we will explain and show you how to find what two numbers have the Greatest Common Factor (GCF) of 640.

There is actually an infinite number of answers to this question. First, note that both the numbers we are looking for must be multiples of 640. Below is the beginning list of multiples of 640 (1 through 7) in numerical order.

1. 640
2. 1280
3. 1920
4. 2560
5. 3200
6. 3840
7. 4480
etc...

Two numbers that have a GCF of 640 can be 640 and any other number on the list above. Thus, two numbers that have a GCF of 640 are:

640 & 1280
640 & 1920
640 & 2560
etc...

That is not all! Any combination of any multiple of 640 and "odd" multiples of 640 will also have GCF of 640. We numbered the multiples above so it would be easy to identify the "odd" multiples (number 1, 3, 5, 7, etc). Thus, here are some more examples of two numbers that also have a GCF of 640.

1280 & 1920
1280 & 3200
2560 & 3200
2560 & 4480
etc...

Like we stated above, there are infinite combinations of two numbers whose GCF is 640. The lists we created can go on forever.

Two numbers have a GCF of Calculator
Need the answer to a similar problem? Enter your GCF below to find the two numbers with that GCF.

Teacher Tip: If you are a teacher, you could ask these questions of your students: "I am thinking of two numbers and the GCF is 640, what are the numbers?" or "What are two numbers whose GCF is 640?"

What two numbers have a GCF of 641?
Need more knowledge? Go here for the next question we explained and solved.