GCF for 21 and 38

What is the Greatest common Divisor of 21 and 38?

Answer: GCF of 21 and 38 is 1

(One)

Finding GCF for 21 and 38 using all factors (divisors) listing

The first method to find GCF for numbers 21 and 38 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 38: 1, 2, 19, 38

So the Greatest Common Factor for 21 and 38 is 1

Finding GCF for 21 and 38 by Prime Factorization

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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 21 and 38? (The answer is: 1). Select the first number (e.g. '21') and the second number (e.g. '38'). 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
6382
7381
8382
9381
10382
11381
12382
13381
1438
15381
16382
17381
1838
1938
20382
2138
22382
23381
2438
25381
2638
2738
28382
29381
30382
31381
32382
33381
3438
35381

FAQ

What is the Greatest common Divisor of 21 and 38?

GCF of 21 and 38 is 1