Is 22 a perfect square?

Can you explain to me why 22 is not considered a perfect square? I understand that a perfect square is a number that can be expressed as the product of an integer with itself, but I'm having trouble seeing why 22 doesn't fit that description. Is there a specific rule or property that 22 lacks that makes it ineligible to be classified as a perfect square? I'm looking for a clear and concise explanation to help me better understand this concept.