GCF for 70 and 640

What is the Greatest Common Factor of 70 and 640?

Answer: GCF of 70 and 640 is 10

(Ten)

Finding GCF for 70 and 640 using all factors (divisors) listing

The first method to find GCF for numbers 70 and 640 is to list all factors for both numbers and pick the highest common one:

All factors of 70: 1, 2, 5, 7, 10, 14, 35, 70

All factors of 640: 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 320, 640

So the Greatest Common Factor for 70 and 640 is 10

Finding GCF for 70 and 640 by Prime Factorization

The second method to find GCF for numbers 70 and 640 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 70: 2, 5, 7

All Prime Factors of 640: 2, 2, 2, 2, 2, 2, 2, 5

As we can see there are Prime Factors common to both numbers: 2, 5

Now we need to multiply them to find GCF: 2 × 5 = 10

GCF Table

Number 1Number 2GCF
556405
566408
576401
586402
596401
6064020
616401
626402
636401
6464064
656405
666402
676401
686404
696401
7064010
716401
726408
736401
746402
756405
766404
776401
786402
796401
8064080
816401
826402
836401
846404

About "Greatest Common Factor" Calculator

This calculator will help you find the greatest common factor (GCF) of two numbers. For example, it can help you find out what is the Greatest Common Factor of 70 and 640? (The answer is: 10). Select the first number (e.g. '70') and the second number (e.g. '640'). After that hit the 'Calculate' button.
Greatest Common Factor (GCF) also known as the Greatest Common Divisor (GCD) or Highest Common Factor (HCF) - it is the largest positive integer that divides each of the integers with zero remainder

FAQ

What is the Greatest Common Factor of 70 and 640?

GCF of 70 and 640 is 10