Yup, that is what happened. I'm working with the mods to remove the duplicates, but it won't fix this particular problem -- the "counter" has already passed the 16.7 million limit we had. Even after removing the duplicates, those IDs won't ever get reused, so we had to fix it anyway.

(And to be clear, when the dupes are removed the profile page will drop back to the number it's supposed to have. The count will be accurate, it's just that the database will have empty spots that it can never re-use.)