What is the Greatest Common Factor of 405 and 421?

Greatest common factor (GCF) of 405 and 421 is 1.

GCF(405,421) = 1

We will now calculate the prime factors of 405 and 421, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 405 and 421.

How to find the GCF of 405 and 421?

We will first find the prime factorization of 405 and 421. After we will calculate the factors of 405 and 421 and find the biggest common factor number .

Step-1: Prime Factorization of 405

Prime factors of 405 are 3, 5. Prime factorization of 405 in exponential form is:

405 = 3⁴ × 5¹

Step-2: Prime Factorization of 421

Prime factors of 421 are 421. Prime factorization of 421 in exponential form is:

421 = 421¹

Step-3: Factors of 405

List of positive integer factors of 405 that divides 405 without a remainder.

1, 3, 5, 9, 15, 27, 45, 81, 135

Step-4: Factors of 421

List of positive integer factors of 421 that divides 405 without a remainder.

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 405 and 421. The biggest common factor number is the GCF number.
So the greatest common factor 405 and 421 is 1.

Also check out the Least Common Multiple of 405 and 421