What is the Greatest Common Factor of 7821 and 7840?

Greatest common factor (GCF) of 7821 and 7840 is 1.

GCF(7821,7840) = 1

We will now calculate the prime factors of 7821 and 7840, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 7821 and 7840.

How to find the GCF of 7821 and 7840?

We will first find the prime factorization of 7821 and 7840. After we will calculate the factors of 7821 and 7840 and find the biggest common factor number .

Step-1: Prime Factorization of 7821

Prime factors of 7821 are 3, 11, 79. Prime factorization of 7821 in exponential form is:

7821 = 3² × 11¹ × 79¹

Step-2: Prime Factorization of 7840

Prime factors of 7840 are 2, 5, 7. Prime factorization of 7840 in exponential form is:

7840 = 2⁵ × 5¹ × 7²

Step-3: Factors of 7821

List of positive integer factors of 7821 that divides 7821 without a remainder.

1, 3, 9, 11, 33, 79, 99, 237, 711, 869, 2607

Step-4: Factors of 7840

List of positive integer factors of 7840 that divides 7821 without a remainder.

1, 2, 4, 5, 7, 8, 10, 14, 16, 20, 28, 32, 35, 40, 49, 56, 70, 80, 98, 112, 140, 160, 196, 224, 245, 280, 392, 490, 560, 784, 980, 1120, 1568, 1960, 3920

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 7821 and 7840. The biggest common factor number is the GCF number.
So the greatest common factor 7821 and 7840 is 1.

Also check out the Least Common Multiple of 7821 and 7840