# Arithmetic Course/Types of Number/Natural Number

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## Natural Number[edit]

Natural Number is a set of all digits from 0 to 9 and beyond

- N = {0,1,2,3,4,5,6,7,8,9,...}

### Even Number[edit]

Natural Number divisible by two is called Even Number

- 2N = {0,2,4,6,8,...}

### Odd Number[edit]

Natural Number not divisible by two is called Odd Number

- 2N + 1 = {1,3,5,7,9,...}

## Prime Number[edit]

prime number "p" is the number that has exactly 2 natural divisors [1 and p]

- p=[2,3,5,7,11,...]