What is the Greatest Common Factor of 155 and 171?

Greatest common factor (GCF) of 155 and 171 is 1.

GCF(155,171) = 1

We will now calculate the prime factors of 155 and 171, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 155 and 171.

How to find the GCF of 155 and 171?

We will first find the prime factorization of 155 and 171. After we will calculate the factors of 155 and 171 and find the biggest common factor number .

Step-1: Prime Factorization of 155

Prime factors of 155 are 5, 31. Prime factorization of 155 in exponential form is:

155 = 5¹ × 31¹

Step-2: Prime Factorization of 171

Prime factors of 171 are 3, 19. Prime factorization of 171 in exponential form is:

171 = 3² × 19¹

Step-3: Factors of 155

List of positive integer factors of 155 that divides 155 without a remainder.

1, 5, 31

Step-4: Factors of 171

List of positive integer factors of 171 that divides 155 without a remainder.

1, 3, 9, 19, 57

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 155 and 171. The biggest common factor number is the GCF number.
So the greatest common factor 155 and 171 is 1.

Also check out the Least Common Multiple of 155 and 171