It is a scam. After getting a couple of calls from this number and no message was left I googled it and saw others who said it was somebody claiming to be from Verizon.
I called the number and the voice sounds just like the one on Verizon's greeting.
I called Verizon and the rep said it was a phishing scam and they are aware of it, obviously. He said they don't use cell numbers to contact customers and advised not to give any information of any kind.