Prime Numbers: 1 TO 20

Prime numbers between 1 to 20

Prime numbers are the numbers that have only two factors which are  the number itself and 1. Eight prime numbers are present between 1 to 20. Now, any number that has more than two factors is called a non-prime ( composite) number. The number 1 is neither a prime nor a composite number.

The eight prime numbers between 1 to 20 are 2, 3, 5, 7, 11, 13, 17, 19.

How do we know that they are prime numbers?

The conditions of a number being a prime number are:

• The number must be divisible by itself and 1.
• It shouldn’t have any other factors.

Now, 

2 = 2 x 1

3 = 3 x 1

5 = 5 x 1

7 = 7 x 1

11 = 11 x 1

13 = 13 x 1

17 = 17 x 1

19 = 19 x 1 

The above numbers satisfy the condition of being a prime number.