GCF for 40 and 390

What is the Greatest common Divisor of 40 and 390?

Answer: GCF of 40 and 390 is 10

(Ten)

Finding GCF for 40 and 390 using all factors (divisors) listing

The first method to find GCF for numbers 40 and 390 is to list all factors for both numbers and pick the highest common one:

All factors of 40: 1, 2, 4, 5, 8, 10, 20, 40

All factors of 390: 1, 2, 3, 5, 6, 10, 13, 15, 26, 30, 39, 65, 78, 130, 195, 390

So the Greatest Common Factor for 40 and 390 is 10

Finding GCF for 40 and 390 by Prime Factorization

The second method to find GCF for numbers 40 and 390 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 40: 2, 2, 2, 5

All Prime Factors of 390: 2, 3, 5, 13

As we can see there are Prime Factors common to both numbers: 2, 5

Now we need to multiply them to find GCF: 2 × 5 = 10

GCF Table

Number 1Number 2GCF
253905
2639026
273903
283902
293901
3039030
313901
323902
333903
343902
353905
363906
373901
383902
3939039
4039010
413901
423906
433901
443902
4539015
463902
473901
483906
493901
5039010
513903
5239026
533901
543906

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 40 and 390? (The answer is: 10). Select the first number (e.g. '40') and the second number (e.g. '390'). 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 40 and 390?

GCF of 40 and 390 is 10