Missed a call from this number, tried to call back a few minutes later to see who it was and got a "this number is not in service" message.

Received a call from this number once, no voicemail left

Received a recorded voice stating I was referenced to receive a home security system. I live in an apartment complex with onsite security.

I got a phone call from this number at 18:55 CET. I missed the call and there was a voice message left of 5 seconds but complete silence.
http://www.instantnumbersearch.com/6783180010/ says it is a call from Atlanta.
City/State/Zip: Atlanta GA, 30328
Phone Type: Land Line
Phone Carrier: Us Lec Of Georgia, Inc.
Nearby Areas: Gainesville Norcross Fairburn Austell Marietta
Time Zone:America/New_York
Last updated:09/30/15

Keeps calling my cell about every other week or so. I never answer unknown numbers.