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What is the prime factorization of the number 4,641?

A:

The prime factors are: 3 x 7 x 13 x 17

or also written as { 3, 7, 13, 17 }

Written in exponential form: 31 x 71 x 131 x 171

Why is the prime factorization of 4,641 written as 31 x 71 x 131 x 171?

What is prime factorization?

Prime factorization or prime factor decomposition is the process of finding which prime numbers can be multiplied together to make the original number.

Finding the prime factors of 4,641

To find the prime factors, you start by dividing the number by the first prime number, which is 2. If there is not a remainder, meaning you can divide evenly, then 2 is a factor of the number. Continue dividing by 2 until you cannot divide evenly anymore. Write down how many 2's you were able to divide by evenly. Now try dividing by the next prime factor, which is 3. The goal is to get to a quotient of 1.

If it doesn't make sense yet, let's try it...

Here are the first several prime factors: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29...

Let's start by dividing 4,641 by 2

4,641 ÷ 2 = 2,320.5 - This has a remainder. Let's try another prime number.

4,641 ÷ 3 = 1,547 - No remainder! 3 is one of the factors!

1,547 ÷ 3 = 515.6667 - There is a remainder. We can't divide by 3 evenly anymore. Let's try the next prime number

1,547 ÷ 5 = 309.4 - This has a remainder. 5 is not a factor.

1,547 ÷ 7 = 221 - No remainder! 7 is one of the factors!

221 ÷ 7 = 31.5714 - There is a remainder. We can't divide by 7 evenly anymore. Let's try the next prime number

221 ÷ 11 = 20.0909 - This has a remainder. 11 is not a factor.

221 ÷ 13 = 17 - No remainder! 13 is one of the factors!

17 ÷ 13 = 1.3077 - There is a remainder. We can't divide by 13 evenly anymore. Let's try the next prime number

17 ÷ 17 = 1 - No remainder! 17 is one of the factors!

The orange divisor(s) above are the prime factors of the number 4,641. If we put all of it together we have the factors 3 x 7 x 13 x 17 = 4,641. It can also be written in exponential form as 31 x 71 x 131 x 171.

Factor Tree

Another way to do prime factorization is to use a factor tree. Below is a factor tree for the number 4,641.

4,641

Factor Arrows

3 1,547

Factor Arrows

7 221

Factor Arrows

13 17

More Prime Factorization Examples

4,639 4,640 4,642 4,643

4,6391 25 x 51 x 291 21 x 111 x 2111 4,6431

name the following angles

(a) ∠1 (b) ∠2 (c) ∠3 (d) ∠1 + ∠2 (e) ∠2 + ∠3

(f) ∠1 + ∠2 + ∠3 (g) ∠CBA – ∠1

answer:

(a) ∠CBD, (b) ∠DBE, (c) ∠EBA, (d) ∠CBE, (e)∠DBA, (f) ∠CBA (g) ∠DBA

What is the HCF and LCM of 12,15,20,27

Answers:

12 = 2×2×3 = 2^2 ×3^1

15 = 3× 5

20 = 2×2×5 = 2^2×5

27 = 3×3×3 = 3^3

HCF = 1

LCM = 2^2 × 3^3 × 5 = 540