Does anyone know what has integers as it's square root?

It shouldn't be too tough to find one of those, seeing that there are

an infinite number of them.

To create one, take any integer, positive or negative, and multiply it by itself.

Here are a few to put you in the mood:

1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225, 256, ...

784, 841, 900, 1024, 1225, 1600, 2500, 3600, 4900, 10000, 1 million, ...