Unitary divisor
Okay kiddo, imagine we have a bunch of numbers. A unitary divisor is a special type of number that can divide another number and give a whole number answer, but it has a special property: it's also a coprime with the other number.
Let me explain what coprime means. You know how some people are friends and some people are not friends? Well, in math, we call numbers "friends" when they have something in common other than themselves and 1. Like 4 and 8 are friends because they both have 2 as a factor. But 3 and 4 are not friends because they don't have any common factors other than 1. The fancy word for having no common factors other than 1 is "coprime".
So a unitary divisor is a friend of another number that can divide it and give a whole number answer, but it's coprime with the other number. That means, if we take any number and we find all its unitary divisors, then those numbers won't have any factors in common other than 1. Cool, right?
Let me explain what coprime means. You know how some people are friends and some people are not friends? Well, in math, we call numbers "friends" when they have something in common other than themselves and 1. Like 4 and 8 are friends because they both have 2 as a factor. But 3 and 4 are not friends because they don't have any common factors other than 1. The fancy word for having no common factors other than 1 is "coprime".
So a unitary divisor is a friend of another number that can divide it and give a whole number answer, but it's coprime with the other number. That means, if we take any number and we find all its unitary divisors, then those numbers won't have any factors in common other than 1. Cool, right?