GCF for 168 and 189

What is the Greatest common Divisor of 168 and 189?

Answer: GCF of 168 and 189 is 21

(Twenty-one)

Finding GCF for 168 and 189 using all factors (divisors) listing

The first method to find GCF for numbers 168 and 189 is to list all factors for both numbers and pick the highest common one:

All factors of 168: 1, 2, 3, 4, 6, 7, 8, 12, 14, 21, 24, 28, 42, 56, 84, 168

All factors of 189: 1, 3, 7, 9, 21, 27, 63, 189

So the Greatest Common Factor for 168 and 189 is 21

Finding GCF for 168 and 189 by Prime Factorization

The second method to find GCF for numbers 168 and 189 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 168: 2, 2, 2, 3, 7

All Prime Factors of 189: 3, 3, 3, 7

As we can see there are Prime Factors common to both numbers: 3, 7

Now we need to multiply them to find GCF: 3 × 7 = 21

GCF Table

Number 1Number 2GCF
1531899
1541897
1551891
1561893
1571891
1581891
1591893
1601891
1611897
16218927
1631891
1641891
1651893
1661891
1671891
168189
1691891
1701891
1711899
1721891
1731891
1741893
1751897
1761891
1771893
1781891
1791891
1801899
1811891
1821897

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 168 and 189? (The answer is: 21). Select the first number (e.g. '168') and the second number (e.g. '189'). 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 168 and 189?

GCF of 168 and 189 is 21