What is the Greatest Common Factor of 615 and 620?

Greatest common factor (GCF) of 615 and 620 is 5.

GCF(615,620) = 5

We will now calculate the prime factors of 615 and 620, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 615 and 620.

How to find the GCF of 615 and 620?

We will first find the prime factorization of 615 and 620. After we will calculate the factors of 615 and 620 and find the biggest common factor number .

Step-1: Prime Factorization of 615

Prime factors of 615 are 3, 5, 41. Prime factorization of 615 in exponential form is:

615 = 3¹ × 5¹ × 41¹

Step-2: Prime Factorization of 620

Prime factors of 620 are 2, 5, 31. Prime factorization of 620 in exponential form is:

620 = 2² × 5¹ × 31¹

Step-3: Factors of 615

List of positive integer factors of 615 that divides 615 without a remainder.

1, 3, 5, 15, 41, 123, 205

Step-4: Factors of 620

List of positive integer factors of 620 that divides 615 without a remainder.

1, 2, 4, 5, 10, 20, 31, 62, 124, 155, 310

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 615 and 620. The biggest common factor number is the GCF number.
So the greatest common factor 615 and 620 is 5.

Also check out the Least Common Multiple of 615 and 620