GCF for 72 and 81

"Greatest Common Factor" Calculator

Greatest Common Factor of

and

What is the Greatest common Divisor of 72 and 81?

Answer: GCF of 72 and 81 is 9

(Nine)

Finding GCF for 72 and 81 using all factors (divisors) listing

The first method to find GCF for numbers 72 and 81 is to list all factors for both numbers and pick the highest common one:

All factors of 72: 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72

All factors of 81: 1, 3, 9, 27, 81

So the Greatest Common Factor for 72 and 81 is 9

Finding GCF for 72 and 81 by Prime Factorization

The second method to find GCF for numbers 72 and 81 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 72: 2, 2, 2, 3, 3

All Prime Factors of 81: 3, 3, 3, 3

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

Now we need to multiply them to find GCF: 3 × 3 = 9

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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 72 and 81? (The answer is: 9). Select the first number (e.g. '72') and the second number (e.g. '81'). 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

"Greatest Common Factor" Calculator

Greatest Common Factor of

and

GCF Table

Number 1Number 2GCF
57813
58811
59811
60813
61811
62811
63819
64811
65811
66813
67811
68811
69813
70811
71811
72819
73811
74811
75813
76811
77811
78813
79811
80811
818181
82811
83811
84813
85811
86811

FAQ

What is the Greatest common Divisor of 72 and 81?

GCF of 72 and 81 is 9

See Also