This number just called me. I did not answer. They didn't hang up in time so my voice mail got a few seconds of silence. No message. Caller from Washington DC.
Spam caller. Spam calls automatically-do-not-ring: On my cell phone, I've installed "Call Blocker Free - Blacklist" by NQ Mobile Security. It is useful for non-business phones to only accept calls from phone numbers I want, incoming unwanted calls automatically do not ring (rings on the spam caller end of the call, but not the recipient end and shows in the app instead of the phone call log). I go to the app>Main screen>Funnel icon>Blocking mode> change it to: "Accept ONLY FROM WHITELIST and CONTACTS". Add the phone numbers you wish to receive calls from to your Contacts (keep your Contacts up-to-date as normal) and/or add non-contacts that you wish to receive a call from to the app Whitelist. With my phone carrier service, I also turn voicemail OFF so that it doesn't pickup a spam call after its set time to record.
UPDATE: I'm liking "Call Blocker" by embware better for the same capabilities; but also with the ability to add a blocked number chosen from the blocked call log to the whitelist, with a name so I know the name associated with the phone number.