Is the last name Cohen (and it’s variants) primarily Jewish?

I know that you can’t really tell if someone is Jewish by their last name, but I haven’t found much about the name Cohen that isn’t Jewish, in this case Kohn. I was looking at my great-grandmother’s Ellis Island records, and her mother’s last name is listed as Kohn. As far as I know my great-grandmother did not practice Judaism, at least when she came to America, but my mom remembers “celebrating” Shabbat (always going over to her grandmother’s house), and helping her making matzo ball soup.