Unknown numbers do not get answered here at our home - sadly, we can't even use our land line and even some scammers get through to our cell phones - sucks the big one, doesn't it? We pay and they can try to scam - we have absolutely no recourse, even though we are on the state and federal do not call lists - they can harass us but we cannot harass them back!
Federal law allows calls from 8 am to 9 pm your time, so unless your state law says different, the time they called you is within legal limits. As to the content of the call, that might be illegal, but that is not what you were asking.
Received call on June 27, 2017 at 1:02 PM although the call was within my area code my caller ID did not reflect the name of the caller so I let it go to voice mail. Call was terminated before my outgoing message was completed.