Before I show you any special guys, you need to be very familiar with some basic perfect squares:
And some perfect cubes:
You should know these cold. If my cat comes into you room some night, wakes you out of a dead sleep and yells, "meow meow meow meow!" OK, pretend that he speaks English and yells, "64! What is it? WHAT IS IT?!" Without even thinking, you should yell, "A perfect square! Don't hurt me!"
(Don't worry. My cat isn't allowed out at night.)
OK -- let's go!