# What is the Greatest Common Factor of 78 and 86?

Greatest common factor (GCF) of 78 and 86 is 2.

GCF(78,86) = 2

We will now calculate the prime factors of 78 and 86, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 78 and 86.

GCF Calculator and
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## How to find the GCF of 78 and 86?

We will first find the prime factorization of 78 and 86. After we will calculate the factors of 78 and 86 and find the biggest common factor number .

### Step-1: Prime Factorization of 78

Prime factors of 78 are 2, 3, 13. Prime factorization of 78 in exponential form is:

78 = 21 × 31 × 131

### Step-2: Prime Factorization of 86

Prime factors of 86 are 2, 43. Prime factorization of 86 in exponential form is:

86 = 21 × 431

### Step-3: Factors of 78

List of positive integer factors of 78 that divides 78 without a remainder.

1, 2, 3, 6, 13, 26, 39

### Step-4: Factors of 86

List of positive integer factors of 86 that divides 78 without a remainder.

1, 2, 43

#### Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 78 and 86. The biggest common factor number is the GCF number.
So the greatest common factor 78 and 86 is 2.

Also check out the Least Common Multiple of 78 and 86