I did not answer it.

8106213661 called up but i did not answer....who is this caller?

caller hang up

I answered, and the person on the other end said, "Uh, hello," and then hung up.  It sounded almost like he didn't expect anyone to answer.  I cannot seem to find any information online telling me who it is, other than a caller from Michigan.

Same thing on my end.

Tried to call the number back and got a recording saying the number had been disconnected or was no longer in service.  Didn't sound right though and I know it was the right number because I dialed it directly back from my cell phone.

Got it too @ 3:09 EST. Said hello, they responded but broke up then nothing....sounds like a phishing scam or compling a list of active numbers to sell.

Whoever it was called me too, but I was in school, and my phone was off, so it just showed up as a missed call. They didn't leave a voicemail, and I haven't tried to call it back.

Ditto.  I didn't answer since I didn't recognize the number, they left 1sec of silence on my voicemail.  Calling the number back ended up in a faked "this number has been disconnected" recording.