I have received only a few calls from this number, but it's got the same area code and next 3 digits as another I had to block.  I will do a reverse look up just to be certain before I block it.

I reported this number on Friday.  They called again this afternoon.  Again, there was no message left.  I did, however, notice that you could hear background noise, such as at a business.
I called them back, got a message about my call being monitored for quality control purposes.  Then, I heard the line go busy.  I hung up and have blocked that number.