A Perfect Square

This is from the wild, wacky, wonderful world of mathematics and it was sent in by William Dubuvitz. Here it is:

One of the mechanics in the garage has a son in high school who is a very bright student and very good in mathematics and computer programming. He stopped by the garage one day after school and his father asked what he was doing in school and his son told him about his latest assignment.

He is supposed to write a computer program to handle very large numbers that could not be handled on a typical hand-held calculator. The teacher told the students to use that program to determine if a certain very large number is a perfect square. (What is a perfect square? A perfect square is a whole number or an integer that is arrived at by squaring another whole number. For example, 900 is a perfect square of 30; 196 is a perfect square of 14. 625 is the perfect square of 25. So there are no fractions, no decimals, no nothing. Just whole numbers allowed.)

Each student is assigned a particular number. This kid's number is 334,912,740,121,562. And the teacher wants to know if this is a perfect square.

His father says, "That's a big number!"

And then out of the inky shadows, who appears but Crusty! And he says, "Oh, your teacher gave you an easy number."

"She did?" said the kid.

"Oh yeah. I can give you the answer right now."

The question is, what did Crusty know?

Think you know? Drop Ray a note!

[ Car Talk Puzzler ]