What is the Greatest Common Factor of 615 and 621?

Greatest common factor (GCF) of 615 and 621 is 3.

GCF(615,621) = 3

We will now calculate the prime factors of 615 and 621, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 615 and 621.

How to find the GCF of 615 and 621?

We will first find the prime factorization of 615 and 621. After we will calculate the factors of 615 and 621 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 621

Prime factors of 621 are 3, 23. Prime factorization of 621 in exponential form is:

621 = 3³ × 23¹

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 621

List of positive integer factors of 621 that divides 615 without a remainder.

1, 3, 9, 23, 27, 69, 207

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 615 and 621. The biggest common factor number is the GCF number.
So the greatest common factor 615 and 621 is 3.

Also check out the Least Common Multiple of 615 and 621