# What are all the factors, the prime factorization, and factor pairs of 21390?

To find the factors of 21390, divide 21390 by each number starting with 1 and working up to 21390

## What is a factor in math ?

Factors are the numbers you multiply together to get another number. For example, the factors of 15 are 3 and 5 because 3 × 5 = 15.

The factors of a number can be positive or negative, but they cannot be zero.

The factors of a number can be used to find out if the number is prime or not.

A prime number is a number that has only two factors: itself and 1. For example, the number 7 is prime because its only factors are 7 and 1.

## List all of the factors of 21390 ?

To calculate the factors of 21390 , you can use the division method.

1. Begin by dividing 21390 by the smallest possible number, which is 2.

2. If the division is even, then 2 is a factor of 21390.

3. Continue dividing 21390 by larger numbers until you find an odd number that does not divide evenly into 21390 .

4. The numbers that divide evenly into 21390 are the factors of 21390 .

Now let us find how to calculate all the factors of Twenty-one thousand three hundred ninety :

21390 ÷ 1 = 21390
21390 ÷ 2 = 10695
21390 ÷ 3 = 7130
21390 ÷ 5 = 4278
21390 ÷ 6 = 3565
21390 ÷ 10 = 2139
21390 ÷ 15 = 1426
21390 ÷ 23 = 930
21390 ÷ 30 = 713
21390 ÷ 31 = 690
21390 ÷ 46 = 465
21390 ÷ 62 = 345
21390 ÷ 69 = 310
21390 ÷ 93 = 230
21390 ÷ 115 = 186
21390 ÷ 138 = 155
21390 ÷ 155 = 138
21390 ÷ 186 = 115
21390 ÷ 230 = 93
21390 ÷ 310 = 69
21390 ÷ 345 = 62
21390 ÷ 465 = 46
21390 ÷ 690 = 31
21390 ÷ 713 = 30
21390 ÷ 930 = 23
21390 ÷ 1426 = 15
21390 ÷ 2139 = 10
21390 ÷ 3565 = 6
21390 ÷ 4278 = 5
21390 ÷ 7130 = 3
21390 ÷ 10695 = 2
21390 ÷ 21390 = 1

As you can see, the factors of 21390 are 1 , 2 , 3 , 5 , 6 , 10 , 15 , 23 , 30 , 31 , 46 , 62 , 69 , 93 , 115 , 138 , 155 , 186 , 230 , 310 , 345 , 465 , 690 , 713 , 930 , 1426 , 2139 , 3565 , 4278 , 7130 , 10695 and 21390 .

## How many factors of 21390 are there ?

The factors of 21390 are the numbers that can evenly divide 21390 . These numbers are 1 , 2 , 3 , 5 , 6 , 10 , 15 , 23 , 30 , 31 , 46 , 62 , 69 , 93 , 115 , 138 , 155 , 186 , 230 , 310 , 345 , 465 , 690 , 713 , 930 , 1426 , 2139 , 3565 , 4278 , 7130 , 10695 and 21390.

Thus, there are a total of 32 factors of 21390

## What are the factor pairs of 21390 ?

Factor Pairs of 21390 are combinations of two factors that when multiplied together equal 21390. There are many ways to calculate the factor pairs of 21390 .

One easy way is to list out the factors of 21390 :
1 , 2 , 3 , 5 , 6 , 10 , 15 , 23 , 30 , 31 , 46 , 62 , 69 , 93 , 115 , 138 , 155 , 186 , 230 , 310 , 345 , 465 , 690 , 713 , 930 , 1426 , 2139 , 3565 , 4278 , 7130 , 10695 , 21390

Then, pair up the factors:
(1,21390),(2,10695),(3,7130),(5,4278),(6,3565),(10,2139),(15,1426),(23,930),(30,713),(31,690),(46,465),(62,345),(69,310),(93,230),(115,186) and (138,155) These are the factor pairs of 21390 .

## Prime Factorisation of 21390

There are a few different methods that can be used to calculate the prime factorization of a number. Two of the most common methods are listed below.

1) Use a factor tree :

1. Take the number you want to find the prime factorization of and write it at the top of the page

2. Find the smallest number that goes into the number you are finding the prime factorization of evenly and write it next to the number you are finding the prime factorization of

3. Draw a line under the number you just wrote and the number you are finding the prime factorization of

4. Repeat step 2 with the number you just wrote until that number can no longer be divided evenly

5. The numbers written on the lines will be the prime factors of the number you started with

For example, to calculate the prime factorization of 21390 using a factor tree, we would start by writing 21390 on a piece of paper. Then, we would draw a line under it and begin finding factors.

The final prime factorization of 21390 would be 2 x 3 x 5 x 23 x 31.

2) Use a factorization method :

There are a few different factorization methods that can be used to calculate the prime factorization of a number.

One common method is to start by dividing the number by the smallest prime number that will divide evenly into it.

Then, continue dividing the number by successively larger prime numbers until the number has been fully factorised.

For example, to calculate the prime factorization of 21390 using this method, we keep dividing until it gives a non-zero remainder.

21390 ÷ 2 = 10695
10695 ÷ 3 = 3565
3565 ÷ 5 = 713
713 ÷ 23 = 31
31 ÷ 31 = 1

So the prime factors of 21390 are 2 x 3 x 5 x 23 x 31.

## Frequently Asked Questions on Factors

### What are all the factors of 21390 ?

The factors of 21390 are 1 , 2 , 3 , 5 , 6 , 10 , 15 , 23 , 30 , 31 , 46 , 62 , 69 , 93 , 115 , 138 , 155 , 186 , 230 , 310 , 345 , 465 , 690 , 713 , 930 , 1426 , 2139 , 3565 , 4278 , 7130 , 10695 and 21390.

### What is the prime factorization of 21390 ?

The prime factorization of 21390 is 2 x 3 x 5 x 23 x 31 or 21 x 31 x 51 x 231 x 311, where 2 , 3 , 5 , 23 , 31 are the prime numbers .

### What are the prime factors of 21390 ?

The prime factors of 21390 are 2 , 3 , 5 , 23 , 31 .

### Is 21390 a prime number ?

A prime number is a number that has only two factors 1 and itself.
21390 it is not a prime number because it has the factors 1 , 2 , 3 , 5 , 6 , 10 , 15 , 23 , 30 , 31 , 46 , 62 , 69 , 93 , 115 , 138 , 155 , 186 , 230 , 310 , 345 , 465 , 690 , 713 , 930 , 1426 , 2139 , 3565 , 4278 , 7130 , 10695 and 21390.