GCF for 100 and 640

What is the Greatest common Divisor of 100 and 640?

Answer: GCF of 100 and 640 is 20

(Twenty)

Finding GCF for 100 and 640 using all factors (divisors) listing

The first method to find GCF for numbers 100 and 640 is to list all factors for both numbers and pick the highest common one:

All factors of 100: 1, 2, 4, 5, 10, 20, 25, 50, 100

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 100 and 640 is 20

Finding GCF for 100 and 640 by Prime Factorization

The second method to find GCF for numbers 100 and 640 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 100: 2, 2, 5, 5

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, 2, 5

Now we need to multiply them to find GCF: 2 × 2 × 5 = 20

GCF Table

Number 1Number 2GCF
856405
866402
876401
886408
896401
9064010
916401
926404
936401
946402
956405
9664032
976401
986402
996401
10064020
1016401
1026402
1036401
1046408
1056405
1066402
1076401
1086404
1096401
11064010
1116401
11264016
1136401
1146402

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 Divisor of 100 and 640? (The answer is: 20). Select the first number (e.g. '100') 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 Divisor of 100 and 640?

GCF of 100 and 640 is 20