I thought my daughter would have been a little older than 7 before she asked me a math question that I couldn’t immediately answer. I was wrong. Here was her question, asked innocently over breakfast one morning:
has
factors, and
is also a factor of
. How many numbers are there that are like that?
It took me about 15 minutes before I could definitely give her an answer.
Rather than spoiling the fun for my readers, I’ll just leave this one unanswered and let you think about it.

Great question!