What is the Greatest Common Factor of 987 and 991?

Greatest common factor (GCF) of 987 and 991 is 1.

GCF(987,991) = 1

We will now calculate the prime factors of 987 and 991, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 987 and 991.

How to find the GCF of 987 and 991?

We will first find the prime factorization of 987 and 991. After we will calculate the factors of 987 and 991 and find the biggest common factor number .

Step-1: Prime Factorization of 987

Prime factors of 987 are 3, 7, 47. Prime factorization of 987 in exponential form is:

987 = 3¹ × 7¹ × 47¹

Step-2: Prime Factorization of 991

Prime factors of 991 are 991. Prime factorization of 991 in exponential form is:

991 = 991¹

Step-3: Factors of 987

List of positive integer factors of 987 that divides 987 without a remainder.

1, 3, 7, 21, 47, 141, 329

Step-4: Factors of 991

List of positive integer factors of 991 that divides 987 without a remainder.

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 987 and 991. The biggest common factor number is the GCF number.
So the greatest common factor 987 and 991 is 1.

Also check out the Least Common Multiple of 987 and 991