Who called from 2136180221

I received a call from this number, and there was no one on the other end--just dead air.  Call finally was disconnected.

Got a call from this number on my cell phone, but it stopped ringing as I reached for it. I wouldn't have answered an unfamiliar number anyway, but the pattern (unknown caller, no message left) earned the caller an automatic block.

Called 3May2017@5:10 & 5:11PM, CID= Wireless Caller. This area code is blocked due to previous spam. There are 2.4 billion robocalls a month. Here are 2 links to robocall related newspaper articles, the 1st about proposals to control it and the 2nd about a spam kingpin who was caught: 1) https://www.washingtonpost.com/news/the-switc ... m=.f04d9d7cf59c
2) https://www.washingtonpost.com/news/the-switc ... m=.ad67786f9c3a

Caller left no number. Number lookup many people reported caller as Calvin Richardson, some reporting he identified himself as DoD. Report to FBI.

Did not leave message. Blocked this number.