What is the Greatest Common Factor of 1987 and 1991?

Greatest common factor (GCF) of 1987 and 1991 is 1.

GCF(1987,1991) = 1

We will now calculate the prime factors of 1987 and 1991, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 1987 and 1991.

How to find the GCF of 1987 and 1991?

We will first find the prime factorization of 1987 and 1991. After we will calculate the factors of 1987 and 1991 and find the biggest common factor number .

Step-1: Prime Factorization of 1987

Prime factors of 1987 are 1987. Prime factorization of 1987 in exponential form is:

1987 = 1987¹

Step-2: Prime Factorization of 1991

Prime factors of 1991 are 11, 181. Prime factorization of 1991 in exponential form is:

1991 = 11¹ × 181¹

Step-3: Factors of 1987

List of positive integer factors of 1987 that divides 1987 without a remainder.

Step-4: Factors of 1991

List of positive integer factors of 1991 that divides 1987 without a remainder.

1, 11, 181

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 1987 and 1991. The biggest common factor number is the GCF number.
So the greatest common factor 1987 and 1991 is 1.

Also check out the Least Common Multiple of 1987 and 1991