I use a software called phonetray - not it is not free, but it works...I simply block the number and add a voice reply like "Not accepting calls" or "Not accepting Telemarking calls" among several options. When this number come in, it rings once and that it! I can block up to 1,000 numbers, and accept the same number by adding them to a white list and have the option of adding a name or some other note to let me know who is calling...it displays on the PC screen, announces the caller name and number...nice.....
This number as well as many others constantly call. I looked up the numbers and they are all robo-calls and telemarketers. A drastic measure I came up with was to not only set up my answering machine to pick up after 2 rings but to also have it hang up. i love it.
I do not answer unknown numbers. Someone called today at 4:30 PM, let it ring 4 times and did not leave a message. My phone number is registered on the national Do Not Call List and I reported this call to them and put this number on my reject list. Based on this website they are trying scam people like us!