What is the prime factorization of 21?

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To calculate the prime factors of 21 enter a number in the field below and press decompose:

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Answer to the Factorization of 21

The factorization of 21 is equal to 3 × 7. We find these factors by successively dividing 21 by the prime numbers until we obtain the prime factors.

Factor Tree of 21

The prime factor tree of 21 is an illustration that shows how the number 21 is decomposed into its fundamental prime factors, as 2, 3 and 5. This visual representation helps you understand the underlying structure of the number and how it is formed from smaller prime numbers.

Look at the following tree:

21
3 7

Steps to Factor the Number 21

1. Division by Smaller Prime Numbers:

Start by dividing the number 21 by the smallest prime numbers, starting with the smallest prime, which is 3.

21 ÷ 3 = 7

2. Obtaining Prime Factors:

Now, the numbers by which you divided 21 and got integer results are the prime factors of 21. In this case, we have 3 and 7.

3. Factorization Expression:

Write the factorization of the number 21 using its prime factors. The full factorization of 21 is:

21 = 3 × 7

These steps show how the number 21 can be factored into its prime components, which is helpful in understanding its structure and mathematical properties.


Links to other factorizations