GCD of 21, 57, 45 Calculator

Given Input numbers are 21, 57, 45

To find the GCD of numbers using factoring list out all the divisors of each number

Divisors of 21

List of positive integer divisors of 21 that divides 21 without a remainder.

1, 3, 7, 21

Divisors of 57

List of positive integer divisors of 57 that divides 57 without a remainder.

1, 3, 19, 57

Divisors of 45

List of positive integer divisors of 45 that divides 45 without a remainder.

1, 3, 5, 9, 15, 45

Greatest Common Divisior

We found the divisors of 21, 57, 45 . The biggest common divisior number is the GCD number.
So the Greatest Common Divisior 21, 57, 45 is 3.

Therefore, GCD of numbers 21, 57, 45 is 3

Given Input Data is 21, 57, 45

Make a list of Prime Factors of all the given numbers initially

Prime Factorization of 21 is 3 x 7

Prime Factorization of 57 is 3 x 19

Prime Factorization of 45 is 3 x 3 x 5

Highest common occurrences in the given inputs are 3¹

Multiplying them we get the GCD as 3

Step1:

Let's calculate the GCD of first two numbers

The formula of GCD is GCD(a, b) = ( a x b) / LCM(a, b)

LCM(21, 57) = 399

GCD(21, 57) = ( 21 x 57 ) / 399

GCD(21, 57) = 1197 / 399

GCD(21, 57) = 3

Step2:

Here we consider the GCD from the above i.e. 3 as first number and the next as 45

The formula of GCD is GCD(a, b) = ( a x b) / LCM(a, b)

LCM(3, 45) = 45

GCD(3, 45) = ( 3 x 45 ) / 45

GCD(3, 45) = 135 / 45

GCD(3, 45) = 3

GCD of 21, 57, 45 is 3

Here are some samples of GCD of Numbers calculations.

• GCD of 96, 91, 19
• GCD of 34, 22, 31
• GCD of 73, 12, 21
• GCD of 19, 17, 14
• GCD of 53, 28, 92

1. What is the GCD of 21, 57, 45?

GCD of 21, 57, 45 is 3

2. Where do I get the detailed procedure to find GCD of 21, 57, 45?

You can find a detailed procedure to find GCD of 21, 57, 45 on our page.

3. How to find GCD of 21, 57, 45 on a calculator?

You can find the GCD of 21, 57, 45 by simply giving the inputs separated by commas and click on the calculate button to avail the Greatest Common Divisor in less time.