GCF for 72 and 138

What is the Greatest common Divisor of 72 and 138?

Answer: GCF of 72 and 138 is 6

(Six)

Finding GCF for 72 and 138 using all factors (divisors) listing

The first method to find GCF for numbers 72 and 138 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 138: 1, 2, 3, 6, 23, 46, 69, 138

So the Greatest Common Factor for 72 and 138 is 6

Finding GCF for 72 and 138 by Prime Factorization

The second method to find GCF for numbers 72 and 138 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 138: 2, 3, 23

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

GCF Table

Number 1Number 2GCF
571383
581382
591381
601386
611381
621382
631383
641382
651381
661386
671381
681382
6913869
701382
711381
721386
731381
741382
751383
761382
771381
781386
791381
801382
811383
821382
831381
841386
851381
861382

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 138? (The answer is: 6). Select the first number (e.g. '72') and the second number (e.g. '138'). 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 72 and 138?

GCF of 72 and 138 is 6