# Prime Number

What is prime number?

A number which is divisible by only itself and 1 is a prime number. So, prime number has only two different factors normally 1 and the number itself.

A whole number having only 2 factors is called the prime number.

The two factors of a prime number are 1 and the number itself.

Let us find all the factors of 2, 3, 5, 7, 11, 13, 17 and 19.

(i) 2 → the factors are 1 and 2.

1 × 2 = 2

2 × 1 = 2

(ii) 3 → the factors are 1 and 3.

1 × 3 = 3

3 × 1 = 3

(iii) 5 → the factors are 1 and 5.

1 × 5 = 5

5 × 1 = 5

(iv) 7 → the factors are 1 and 7.

1 × 7 = 7

7 × 1 = 7

(v) 11 → the factors are 1 and 11.

1 × 11 = 11

11 × 1 = 11

(vi) 13 → the factors are 1 and 13.

1 × 13 = 13

13 × 1 = 13

(v) 17 → the factors are 1 and 17.

1 × 17 = 17

17 × 1 = 17

(vi) 19 → the factors are 1 and 19.

1 × 19 = 19

19 × 1 = 19

Therefore,

2 is divisible only by 1 and 2. Therefore, the factors of 2 are 1 and 2.

3 is divisible only by 1 and 3. Therefore, the factors of 3 are 1 and 3.

5 is divisible only by 1 and 5. Therefore, the factors of 5 are 1 and 5.

7 is divisible only by 1 and 7. Therefore, the factors of 7 are 1 and 7.

11 is divisible only by 1 and 11. Therefore, the factors of 11 are 1 and 11.

13 is divisible only by 1 and 13. Therefore, the factors of 13 are 1 and 13.

17 is divisible only by 1 and 17. Therefore, the factors of 17 are 1 and 17.

19 is divisible only by 1 and 19. Therefore, the factors of 19 are 1 and 19.

Thus 2, 3, 5, 7, 11, 13, 17 and 19 are prime numbers.

Note:

(i) All prime numbers except 2, are always odd numbers.

(ii) The number 2 is a prime as well as an even number.

(iii) All prime numbers are exactly divisible by 1 and the number itself.

Didn't find what you were looking for? Or want to know more information about Math Only Math. Use this Google Search to find what you need.

## Recent Articles

1. ### Thousandths Place in Decimals | Decimal Place Value | Decimal Numbers

Jul 20, 24 03:45 PM

When we write a decimal number with three places, we are representing the thousandths place. Each part in the given figure represents one-thousandth of the whole. It is written as 1/1000. In the decim…

2. ### Hundredths Place in Decimals | Decimal Place Value | Decimal Number

Jul 20, 24 02:30 PM

When we write a decimal number with two places, we are representing the hundredths place. Let us take plane sheet which represents one whole. Now, we divide the sheet into 100 equal parts. Each part r…

3. ### Tenths Place in Decimals | Decimal Place Value | Decimal Numbers

Jul 20, 24 12:03 PM

The first place after the decimal point is tenths place which represents how many tenths are there in a number. Let us take a plane sheet which represents one whole. Now, divide the sheet into ten equ…

4. ### Representing Decimals on Number Line | Concept on Formation of Decimal

Jul 20, 24 10:38 AM

Representing decimals on number line shows the intervals between two integers which will help us to increase the basic concept on formation of decimal numbers.