**Question: **What Are Pythagorean Numbers?

**Answer: **The Pythagoreans believed that certain numbers had special properties. The numbers with these properties are called Pythagorean numbers.

- Those numbers whose factors added together equal the number themselves were
**perfect numbers**.
6 is a perfect number because its factors (1 + 2 + 3) equal 6.

**Amicable numbers** were those numbers whose factors added up to one another's: 220 (1 + 2 + 4 + 5 + 10 + 11 + 20 + 22 + 44 + 55 + 110 = 284) 284 (1+ 2 + 4 + 71 + 142 = 220).

Source: Encyclopedia Britannica.

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