My Google Nexus 5X reported the incoming calls as suspected SPAM. I didn't answer and have since blocked the number.

They keep calling and calling and calling..........ad nauseum

Caller ID shows maximum research. Calls repeatedly and hangs up.

Same as all of the above...

Definitely a robocall. I always just let these things go to voicemail, but this one amused me. I supposed the caller "got a talkin' to" from his previous victim and was unaware he was already on another call. The voicemail was a confused/amused male saying to himself, or perhaps a coworker, "I don't understand the question 'Are you standing next to Vladimir Putin?'." Legitimate question considering the communists are totally responsible for the recent influx of telemarketer calls. Way to go, McCarthy.