GCF for 81 and 90

"Greatest Common Factor" Calculator

Greatest Common Factor of

and

What is the Greatest common Divisor of 81 and 90?

Answer: GCF of 81 and 90 is 9

(Nine)

Finding GCF for 81 and 90 using all factors (divisors) listing

The first method to find GCF for numbers 81 and 90 is to list all factors for both numbers and pick the highest common one:

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

All factors of 90: 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90

So the Greatest Common Factor for 81 and 90 is 9

Finding GCF for 81 and 90 by Prime Factorization

The second method to find GCF for numbers 81 and 90 is to list all Prime Factors for both numbers and multiply the common ones:

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

All Prime Factors of 90: 2, 3, 3, 5

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 81 and 90? (The answer is: 9). Select the first number (e.g. '81') and the second number (e.g. '90'). 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
66906
67901
68902
69903
709010
71901
729018
73901
74902
759015
76902
77901
78906
79901
809010
81909
82902
83901
84906
85905
86902
87903
88902
89901
909090
91901
92902
93903
94902
95905

FAQ

What is the Greatest common Divisor of 81 and 90?

GCF of 81 and 90 is 9

See Also