Prime number is one that cannot be decomposed into factors except 1 and itself(numbers 2 3 5 7 are prime.) see factoring

**Explanation**:

All natural numbers have at least two factors: one and the same. see what is a divisor

There are numbers that also have other factors

Examples:

- 15 = 1·15 = 3·5 (
**factors of 15**: 1,3,5,15)

- 12 = 1·12 = 2·6 = 3·4 (
**factors of 12**: 1,2,3,4,6,12)

- 7 = 1·7 (
**factors of 7**: 1,7)

In this example, the number **7 is prime** because it only can be factorized by 1 and itself

A number is prime if there aren’t more factors than **itself and unity**.

**Conclusions**

Prime number is one that can not be obtained by the multiplication of

2 numbers. (Except the same by 1) see what is a multiple

Prime number is the number that can not be obtained by

multiplesof any number (except 1 and itself)

In this table we can see:

In red the **multiples of 2** except 2

In blue **multiples of 3** except 3

In green **multiples of 5** except 5

and so on, with **7** (red triangle), **11** (blue triangle), **13** (green triangle) **…**

The numbers have remained unchecked are the **prime numbers up to 30**, finds that none can be decomposed into prime factors. see factoring