Who called from 2120000005

I too am in Tennessee, have never seen this number before

Yes ! I KEEP getting these calls, even on my cell phone number.

5 a.m. in the morning. Can't call back.  Tennessee recipient.

Called at 4:53 AM.  Fortunately the phone doesn't ring in my bedroom.

I got the recorded message from this number at 2:46am on 6/6 - the id where caller would normally appear was a letter followed by a string of 14 numbers.  I did file a complaint on the FTC site.