What is the Greatest Common Factor of 420 and 436?

Greatest common factor (GCF) of 420 and 436 is 4.

GCF(420,436) = 4

We will now calculate the prime factors of 420 and 436, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 420 and 436.

How to find the GCF of 420 and 436?

We will first find the prime factorization of 420 and 436. After we will calculate the factors of 420 and 436 and find the biggest common factor number .

Step-1: Prime Factorization of 420

Prime factors of 420 are 2, 3, 5, 7. Prime factorization of 420 in exponential form is:

420 = 2² × 3¹ × 5¹ × 7¹

Step-2: Prime Factorization of 436

Prime factors of 436 are 2, 109. Prime factorization of 436 in exponential form is:

436 = 2² × 109¹

Step-3: Factors of 420

List of positive integer factors of 420 that divides 420 without a remainder.

1, 2, 3, 4, 5, 6, 7, 10, 12, 14, 15, 20, 21, 28, 30, 35, 42, 60, 70, 84, 105, 140, 210

Step-4: Factors of 436

List of positive integer factors of 436 that divides 420 without a remainder.

1, 2, 4, 109, 218

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 420 and 436. The biggest common factor number is the GCF number.
So the greatest common factor 420 and 436 is 4.

Also check out the Least Common Multiple of 420 and 436