Zero, right?

But it’s complicated again! Is it prime or composite?

I was having a look-around on Math Stack Exchange Is zero a prime number? and it was absolutely confusing. Give it a read!

It’s not prime, so it should b —

*(Screech sound)*

Wait. Who said it was PRIME? Not me. Let’s prove it!

If zero was prime, then it has no divisors. Let’s see, it has divisors of 0, 1, 2 (2*0=0), 3, 4, 5, 6, 7, 8, 9, 10, blah blah blah, so it’s not prime!

So it’s … composite?

Maybe? I mean we just proved it’s not prime, so it should be composite, right?

There’s a program on Khan Academy called Level 10: Fermat Primality Test and it says composite!

Q.E.D.

*P.S.* Comment below on what you think 0 is.