What is the Greatest Common Factor of 621 and 630?

Greatest common factor (GCF) of 621 and 630 is 9.

GCF(621,630) = 9

We will now calculate the prime factors of 621 and 630, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 621 and 630.

How to find the GCF of 621 and 630?

We will first find the prime factorization of 621 and 630. After we will calculate the factors of 621 and 630 and find the biggest common factor number .

Step-1: Prime Factorization of 621

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

621 = 3³ × 23¹

Step-2: Prime Factorization of 630

Prime factors of 630 are 2, 3, 5, 7. Prime factorization of 630 in exponential form is:

630 = 2¹ × 3² × 5¹ × 7¹

Step-3: Factors of 621

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

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

Step-4: Factors of 630

List of positive integer factors of 630 that divides 621 without a remainder.

1, 2, 3, 5, 6, 7, 9, 10, 14, 15, 18, 21, 30, 35, 42, 45, 63, 70, 90, 105, 126, 210, 315

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 621 and 630. The biggest common factor number is the GCF number.
So the greatest common factor 621 and 630 is 9.

Also check out the Least Common Multiple of 621 and 630