Not a good idea to call those numbers back. more times than not, they want to see if they can get a live person to answer or call back like you did. The "remove" feature is BS.
If I don't recognize the number and they don't leave a message, it's into the block caller bin for them!
I called this number back and it's some kind of telemarket program. "You have received a reward for visiting one of our affilitiate sites" so something of the sort. I pushed the "remove" button, so we will see.