I received a call from this number and missed it. I tried to call back and it said that this number is not a working number and to try back again? Is this a scam?
Yes it is a scam! Microsoft would not call you or anyone out of the blue like that. They'd have no way of knowing that you or anyone else is having any computer troubles unless you initiated the call to their actual customer Tech Support number (which the one that called you most definitely is not).
Those calling you are scammers that are attempting to use Remote Desktop to access you computer in order to install some kind of virus and possibly steal whatever personal information you may have on your system... and then charge you for it.
Microsoft themselves have even warned of these scams:
Told the guy if I need help I'll call my relative who works for Microsoft. He said I can I talk to your relative? I told him I'm in Arizona and Microsoft is in Redmond WA, but you know that right? He hung up! That guy could starve unless he gets paid by the call!