GCF for 66 and 78

What is the Greatest common Divisor of 66 and 78?

Answer: GCF of 66 and 78 is 6

(Six)

Finding GCF for 66 and 78 using all factors (divisors) listing

The first method to find GCF for numbers 66 and 78 is to list all factors for both numbers and pick the highest common one:

All factors of 66: 1, 2, 3, 6, 11, 22, 33, 66

All factors of 78: 1, 2, 3, 6, 13, 26, 39, 78

So the Greatest Common Factor for 66 and 78 is 6

Finding GCF for 66 and 78 by Prime Factorization

The second method to find GCF for numbers 66 and 78 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 66: 2, 3, 11

All Prime Factors of 78: 2, 3, 13

As we can see there are Prime Factors common to both numbers: 2, 3

Now we need to multiply them to find GCF: 2 × 3 = 6

See Also

GCF Table

Number 1Number 2GCF
51783
5278
53781
5478
55781
56782
57783
58782
59781
6078
61781
62782
63783
64782
6578
6678
67781
68782
69783
70782
71781
72786
73781
74782
75783
76782
77781
787878
79781
80782

About "Greatest Common Factor" Calculator

This calculator will help you find the greatest common factor (GCF) of two numbers. For example, it can help you find out what is the Greatest common Divisor of 66 and 78? (The answer is: 6). Select the first number (e.g. '66') and the second number (e.g. '78'). After that hit the 'Calculate' button.
Greatest Common Factor (GCF) also known as the Greatest Common Divisor (GCD) or Highest Common Factor (HCF) - it is the largest positive integer that divides each of the integers with zero remainder

FAQ

What is the Greatest common Divisor of 66 and 78?

GCF of 66 and 78 is 6