What are all factors of 36 that are also square numbers?

Oh, what a happy little question! Let's see here... the factors of 36 are 1, 2, 3, 4, 6, 9, 12, 18, and 36. Now, the square numbers among these factors are 1, 4, and 9. Isn't it wonderful how numbers can come together like this? Just like painting a beautiful picture!