as of today I have received 7 calls from this number.  Did not answer any of them and no message left on recorder

Call back gets, "the person you are trying to reach has a voicemail box that has not been set up yet."  Does that sound like a legitimate, professional call to you?  Certainly doesn't sound like one to me.  This is the google voice mail message for exactly what it sounds like, the mailbox has not be setup.  Spells scam in my book.  Blocked.

None Left, just hangs up :o

Scam