GCF for 72 and 90

What is the Greatest common Divisor of 72 and 90?

Answer: GCF of 72 and 90 is 18

(Eighteen)

Finding GCF for 72 and 90 using all factors (divisors) listing

The first method to find GCF for numbers 72 and 90 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 90: 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90

So the Greatest Common Factor for 72 and 90 is 18

Finding GCF for 72 and 90 by Prime Factorization

The second method to find GCF for numbers 72 and 90 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 90: 2, 3, 3, 5

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

Now we need to multiply them to find GCF: 2 × 3 × 3 = 18

See Also

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 90? (The answer is: 18). Select the first number (e.g. '72') 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

GCF Table

Number 1Number 2GCF
57903
58902
59901
6090
61901
62902
6390
64902
6590
6690
67901
68902
69903
7090
71901
7290
73901
74902
7590
76902
77901
7890
79901
8090
8190
82902
83901
8490
85905
86902

FAQ

What is the Greatest common Divisor of 72 and 90?

GCF of 72 and 90 is 18