This number called my cell phone and it was a recorded message telling me to dial this same number back it is the "IRS's". They urgently need to speak to me.  I called it - because I was feeling spunky - and a man with a heavy unintelligible heavy accented voice says, "Who is calling please".  I just hung up.

I got the same message (computer generated voice), but didn't call back.

First of all, the Federal Government would ask to call a TOLL FREE number, specify the issue (re: your invoice #, your appointment with..., your inquiry, etc) and provide some other helpful information. If the number were a direct line (not a toll free line), it would include a name of the person who is calling and more detail, indicating that this is a follow up on the issue already known to both sides of the call.

That said, in two days four identical messages were received from this number, listed as located in Dumont, NJ. The voice is robotic and obviously created by an amateur.

Don't fall for the scam, this is not IRS calling you.

Do not call this number back. Called and it rang a few times and then went dead. Obviously this is some kind of scam.

Same call asking it was urgent to call them (IRS) back.
I called back and basically hung up after it appeared suspicious from the IRS.