What is the Greatest Common Factor of 12405 and 12420?

Greatest common factor (GCF) of 12405 and 12420 is 15.

GCF(12405,12420) = 15

We will now calculate the prime factors of 12405 and 12420, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 12405 and 12420.

How to find the GCF of 12405 and 12420?

We will first find the prime factorization of 12405 and 12420. After we will calculate the factors of 12405 and 12420 and find the biggest common factor number .

Step-1: Prime Factorization of 12405

Prime factors of 12405 are 3, 5, 827. Prime factorization of 12405 in exponential form is:

12405 = 3¹ × 5¹ × 827¹

Step-2: Prime Factorization of 12420

Prime factors of 12420 are 2, 3, 5, 23. Prime factorization of 12420 in exponential form is:

12420 = 2² × 3³ × 5¹ × 23¹

Step-3: Factors of 12405

List of positive integer factors of 12405 that divides 12405 without a remainder.

1, 3, 5, 15, 827, 2481, 4135

Step-4: Factors of 12420

List of positive integer factors of 12420 that divides 12405 without a remainder.

1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, 23, 27, 30, 36, 45, 46, 54, 60, 69, 90, 92, 108, 115, 135, 138, 180, 207, 230, 270, 276, 345, 414, 460, 540, 621, 690, 828, 1035, 1242, 1380, 2070, 2484, 3105, 4140, 6210

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 12405 and 12420. The biggest common factor number is the GCF number.
So the greatest common factor 12405 and 12420 is 15.

Also check out the Least Common Multiple of 12405 and 12420