GCF for 15 and 70

What is the Greatest common Divisor of 15 and 70?

Answer: GCF of 15 and 70 is 5

(Five)

Finding GCF for 15 and 70 using all factors (divisors) listing

The first method to find GCF for numbers 15 and 70 is to list all factors for both numbers and pick the highest common one:

All factors of 15: 1, 3, 5, 15

All factors of 70: 1, 2, 5, 7, 10, 14, 35, 70

So the Greatest Common Factor for 15 and 70 is 5

Finding GCF for 15 and 70 by Prime Factorization

The second method to find GCF for numbers 15 and 70 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 15: 3, 5

All Prime Factors of 70: 2, 5, 7

As we can see there is only one Prime Factor common to both numbers. It is 5

So 5 is the Greatest Common Factor of 15 and 70

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 15 and 70? (The answer is: 5). Select the first number (e.g. '15') and the second number (e.g. '70'). 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
1701
2702
3701
4702
5705
6702
7707
8702
9701
107010
11701
12702
13701
1470
1570
16702
17701
18702
19701
2070
2170
22702
23701
24702
2570
26702
2770
2870
29701
3070

FAQ

What is the Greatest common Divisor of 15 and 70?

GCF of 15 and 70 is 5