The numbers that call you and you answer and they hang up are actually part of the patroit act and used to monitor suspects the the NSA is keeping tabs on. If you have recieved a call from this number or any numbers that call you then hang up, you need to think what does the NSA want with you.
Wow paranoid much. People get calls like this day in and day out most are debt collectors trying to collect on debts that people refuse to pay for this or that and the original companies write off. If you think this is the NSA then man you need to go back to your group witht eh tin foil helmets and CIA conspiracies.
I hit *67 call block and called this number back - I got a fast busy tone which is also a DISCO signal (disconnected).
No legitimate company does this kind of telemarketing. I guarantee its a scam telemarketer phishing for numbers that answer so they can then resell your number as a live human number to other scam ripoff telemarketers.
Never answer a call from an unfamiliar number. Caller ID is there for a purpose. Use it.