Got a call on my cell phone from this number on Tues. March 18 during the day.  No message left, but verizon tells me it's from Monroe, NC

This number called me on march 19th at 7:31 eastern time on cell with a Michigan area code. I answer and no one is there. It wasn't disconnected, just no one there. I called it back today, march 26th, out of curiosity and it's a non working number. I don't get it. What is the point of this? Is this like emails that come with a virus? You open it and your computer is infected. You answer this and your phone gets a virus or spyware or something? I really wonder. I back up my phone regularly.

Received call at 1:30 cst. I did not answer

Called son's cell.  He didn't answer and they left no message.