What is the Greatest Common Factor of 391 and 402?

Greatest common factor (GCF) of 391 and 402 is 1.

GCF(391,402) = 1

We will now calculate the prime factors of 391 and 402, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 391 and 402.

How to find the GCF of 391 and 402?

We will first find the prime factorization of 391 and 402. After we will calculate the factors of 391 and 402 and find the biggest common factor number .

Step-1: Prime Factorization of 391

Prime factors of 391 are 17, 23. Prime factorization of 391 in exponential form is:

391 = 17¹ × 23¹

Step-2: Prime Factorization of 402

Prime factors of 402 are 2, 3, 67. Prime factorization of 402 in exponential form is:

402 = 2¹ × 3¹ × 67¹

Step-3: Factors of 391

List of positive integer factors of 391 that divides 391 without a remainder.

1, 17, 23

Step-4: Factors of 402

List of positive integer factors of 402 that divides 391 without a remainder.

1, 2, 3, 6, 67, 134, 201

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 391 and 402. The biggest common factor number is the GCF number.
So the greatest common factor 391 and 402 is 1.

Also check out the Least Common Multiple of 391 and 402