NO. It is NOT "activated by visiting an affilated website" because I DO NOT use my phone to 'visit websites' and I do NOT give out the number to ANYONE except family, VERY close friends and the occasional doctor. I CERTAINLY do not 'enter' it into websites so that I can be SPAMMED. THIS IS unwanted, unsolicited SPAM, and therefore ILLEGAL.
Called my on my pre-paid phone on 5/3/14, but, fortunately, I was doing yard work, so didn't hear it and didn't see it until the next day. I will BLOCK it, so they cannot bother me again.