What Makes a Number 'Prime'?

Imagine you have a group of marbles, and you want to divide them into equal piles. If the number of marbles is prime, like 7 or 11, you can’t split them evenly unless you use just one pile, because no other number divides them perfectly.

What’s a Prime Number?

A prime number is a number greater than 1 that has only two factors: 1 and itself. That means it doesn’t break apart into smaller whole numbers in any other way. Numbers like 4 or 6 are not prime because they can be split evenly by more than just 1 and themselves.

Why Do We Care?

Prime numbers help us understand patterns in math, and they’re used all over the place, even in your phone when it connects to Wi-Fi!

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Examples

If you have 7 marbles, you can’t split them evenly among two or more people without breaking one marble.
A prime number is like a secret code, it has only one special pair of numbers that make it work.
You can’t find any other numbers (except for 1) that divide into 13 exactly.

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Categories: Math · prime numbers,math concepts,number theory