What is the Greatest Common Factor of 28405 and 28420?

Greatest common factor (GCF) of 28405 and 28420 is 5.

GCF(28405,28420) = 5

We will now calculate the prime factors of 28405 and 28420, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 28405 and 28420.

How to find the GCF of 28405 and 28420?

We will first find the prime factorization of 28405 and 28420. After we will calculate the factors of 28405 and 28420 and find the biggest common factor number .

Step-1: Prime Factorization of 28405

Prime factors of 28405 are 5, 13, 19, 23. Prime factorization of 28405 in exponential form is:

28405 = 5¹ × 13¹ × 19¹ × 23¹

Step-2: Prime Factorization of 28420

Prime factors of 28420 are 2, 5, 7, 29. Prime factorization of 28420 in exponential form is:

28420 = 2² × 5¹ × 7² × 29¹

Step-3: Factors of 28405

List of positive integer factors of 28405 that divides 28405 without a remainder.

1, 5, 13, 19, 23, 65, 95, 115, 247, 299, 437, 1235, 1495, 2185, 5681

Step-4: Factors of 28420

List of positive integer factors of 28420 that divides 28405 without a remainder.

1, 2, 4, 5, 7, 10, 14, 20, 28, 29, 35, 49, 58, 70, 98, 116, 140, 145, 196, 203, 245, 290, 406, 490, 580, 812, 980, 1015, 1421, 2030, 2842, 4060, 5684, 7105, 14210

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 28405 and 28420. The biggest common factor number is the GCF number.
So the greatest common factor 28405 and 28420 is 5.

Also check out the Least Common Multiple of 28405 and 28420