It may be internet marketing spammers.  I suddenly started receiving spam calls when I registered a domain name, and ICANN regulations require correct phone information.  I got one call from a business involved in setting up websites.  

After I told them to remove me from their list, I started getting a rash of spam phone calls.  Seems as though by answering the first call I confirmed they had a live number, and just like email spammers, that's all they needed to sell my information to everyone and their uncle.

Chances are this is a number for a company to promote ways or services to make money on the internet.

Keep getting calls from this number but no message
if you are going to call please leave a message like "i have the wrong number"
or just leave a message
thanks

Some kind of message service yet they don't leave a message so they must be political.

I won't ever answer a call that I don't know who it is first.

They leave no message so there is no possible return call about what ever they are trying to sell you.

Since I do a lot of survey's this is where most if not all unknow calls come from.