Who called from 7816136500

It's a calling card, I don't know if there is a way to find out the real number they are calling from

It is the ID of a calling card  Co located in MA...and the caller could be anyone you  may know or not.
It is one of the cheapest calling card in MA around $ 0.03 a minute and  can be used in any state to call anywhere in the US.
It isn't very likely to be a telemarketer because  0.03 a minute is too expensive for them to call thousands of numbers a day.
A friend of mine uses this card to call me from 30 miles away in FL...rather than pay $ 0.12 to the local telco.

This is definately a calling card. just recieved a call from this number,tried to call back,disconnected. it was an old family friend of 30 years.he started leaving a message,we got disconnected and i tried to call him back but it wouldnt go through.7816136500. that is all this is. looked it up on google and found this page.

I have received a call from an unknown telephone 781-613-6500. Could you, please, help to stop these calls. Thank you.

Even though they called one time at 3 in the morning.... it was a lady asking to speak to Paul... I live in North Carolina... it could have been a legit wrong number.... so far they've only called one time...