Anybody Knows the Logic To Find Out a Number is Perfect Square or not?

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Fastest way to determine if an integer's square root is an integer

Does Anybody Knows the Logic To Find Out a Number is Perfect Square or not ? (Other than Newtons Method or Synthetic Division Method)

For Eg:- 4, 16, 36, 64 are Perfect Squares.

I will be giving the input as 441, logic should say whether its a Perfect Square or not.

It was a question asked in Amazon Interview.

I would like to do it with out any built in functions