What is the Greatest Common Factor of 6420 and 6440?

Greatest common factor (GCF) of 6420 and 6440 is 20.

GCF(6420,6440) = 20

We will now calculate the prime factors of 6420 and 6440, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 6420 and 6440.

How to find the GCF of 6420 and 6440?

We will first find the prime factorization of 6420 and 6440. After we will calculate the factors of 6420 and 6440 and find the biggest common factor number .

Step-1: Prime Factorization of 6420

Prime factors of 6420 are 2, 3, 5, 107. Prime factorization of 6420 in exponential form is:

6420 = 2² × 3¹ × 5¹ × 107¹

Step-2: Prime Factorization of 6440

Prime factors of 6440 are 2, 5, 7, 23. Prime factorization of 6440 in exponential form is:

6440 = 2³ × 5¹ × 7¹ × 23¹

Step-3: Factors of 6420

List of positive integer factors of 6420 that divides 6420 without a remainder.

1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60, 107, 214, 321, 428, 535, 642, 1070, 1284, 1605, 2140, 3210

Step-4: Factors of 6440

List of positive integer factors of 6440 that divides 6420 without a remainder.

1, 2, 4, 5, 7, 8, 10, 14, 20, 23, 28, 35, 40, 46, 56, 70, 92, 115, 140, 161, 184, 230, 280, 322, 460, 644, 805, 920, 1288, 1610, 3220

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 6420 and 6440. The biggest common factor number is the GCF number.
So the greatest common factor 6420 and 6440 is 20.

Also check out the Least Common Multiple of 6420 and 6440