I'm not sure how many exactly, [ She bites down on another piece of bread, feet swaying around just a little. ] But there are many that have been to Earth. Some with good intention, others not so much. Their presence has not been kept a secret for a long time.

I would say Kryptonians are the most popular among Humans, even though there aren't many of them. That's because Superman is Kryptonian, and he's a superhero. He's very well-liked.