I used to live in Phoenix AZ and had my number registered with tons of businesses... for a while, all was okay, then along came some stuff that required my personal "real estate" business dealings to be posted in some "public places" and that is when the fun began...
I finally figured out if I answer the call and then hit the 5 digit or the # key about 5 times in a row, the calling computer goes away and don't bother me anymore.
But, my phone number was in a major telemarketing database and I was hit with numerous telemarketers. My first instinct was to just block all calls not in my Contacts List.
But, my wife is type II diabetic and we have a lot of medical offices calling us from numbers I don't have in my Contacts List.... so blocking mode was out.
I finally just had the phone number changed to a rural area code, and am guarding it fastidiously... knock on wood, only a few random miss-dials so far.
____________________________________
2 ea. Verizon Galaxy S5, 4.4.4 forever!, ART
MyPhoneExplorer lets you access a broken phone while locked
Nova Prime, Textra, Blue Mail, Qi wireless equipped
MacroDroid can help extend battery life
MacroDroid senses Screen off, turns Wifi & Data OFF
MacroDroid senses Screen on, turns WiFi & Data ON