ELI5: Explain Like I'm 5

Amicable numbers

Okay kiddo, have you heard of numbers before? They're like little symbols that we use to count things. Well, sometimes two numbers are called amicable when they like each other a lot and can be good friends. How do we know if they're friends?

Well, let's say we have a number like 220. If we take all the numbers that divide into it (like 1, 2, 4, 5, 10, 11, 20, 22, 44, 55, and 110) and add them up, we get 284. Guess what? 284 is friends with 220 too! If we take all the numbers that divide into it (like 1, 2, 4, 71, and 142) and add them up, guess what we get? That's right, 220!

So 220 and 284 are amicable numbers because they can be good friends and it's neat because they happen to add up to each other when we take the numbers that divide into them and add them up. There are a lot of other amicable number pairs out there too, but finding them can be tricky. But isn't it cool that numbers can be friends too?
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