GCF for 21 and 61

What is the Greatest Common Factor of 21 and 61?

Answer: GCF of 21 and 61 is 1

(One)

Finding GCF for 21 and 61 using all factors (divisors) listing

The first method to find GCF for numbers 21 and 61 is to list all factors for both numbers and pick the highest common one:

All factors of 21: 1, 3, 7, 21

All factors of 61: 1, 61

So the Greatest Common Factor for 21 and 61 is 1

Finding GCF for 21 and 61 by Prime Factorization

GCF Table

Number 1Number 2GCF
6611
7611
8611
9611
10611
11611
12611
13611
14611
15611
16611
17611
18611
19611
20611
21611
22611
23611
24611
25611
26611
27611
28611
29611
30611
31611
32611
33611
34611
35611

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 Factor of 21 and 61? (The answer is: 1). Select the first number (e.g. '21') and the second number (e.g. '61'). 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 Factor of 21 and 61?

GCF of 21 and 61 is 1