What prime numbers are

What prime numbers are

Definition of number: a number is each one of the abstract entities that form an ordered series and that indicate the quantity of elements in a group

Definition of prime number: a number is prime when it is an integer, it is not 0 or 1, and it can be evenly divided only by itself and by 1.

Examples:

Factors of 3= {1, 3} => 3 is prime
F(7)={1, 7} => it's prime
F(9)={1, 3, 9} => it isn't prime, it can be divided by 3 apart from 1 and 9 Notes:

Number 1 is considered a prime in many cases, although it has only one factor. It depends on the lists, definitions, books or "cultures" whether it is considered a prime or not. Ancient Greeks considered it to be the unit, not a number. We do not consider it a prime.

Number 2 is prime; it is the only even prime.

Twin numbers: The prime numbers that differ by 2 (Ex 5 is prime and 7 is prime, 7-5=2; 31-29=2, etc)

Mersenne primes: prime numbers of the form N=(2^n)-1 where n is an integer and N is the Mersenne prime. There are only 37 known.

Prime numbers endings