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What is the Greatest Common Factor of 1981 and 1987?

Greatest common factor (GCF) of 1981 and 1987 is 1.

GCF(1981,1987) = 1

We will now calculate the prime factors of 1981 and 1987, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 1981 and 1987.

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How to find the GCF of 1981 and 1987?

We will first find the prime factorization of 1981 and 1987. After we will calculate the factors of 1981 and 1987 and find the biggest common factor number .

Step-1: Prime Factorization of 1981

Prime factors of 1981 are 7, 283. Prime factorization of 1981 in exponential form is:

1981 = 71 × 2831

Step-2: Prime Factorization of 1987

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

1987 = 19871

Step-3: Factors of 1981

List of positive integer factors of 1981 that divides 1981 without a remainder.

1, 7, 283

Step-4: Factors of 1987

List of positive integer factors of 1987 that divides 1981 without a remainder.

1

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 1981 and 1987. The biggest common factor number is the GCF number.
So the greatest common factor 1981 and 1987 is 1.

Also check out the Least Common Multiple of 1981 and 1987