I wanted to clarify a quick point: when people search for a phone number and land on a page like the one below, it’s not really useful and a bad user experience. Also, we do consider it to be keyword stuffing to put so many phone numbers on a page.
There are a few websites that provide value-add for some phone numbers, e.g. sites that let people discuss a specific phone number that keeps calling them over and over. But if a site stuffs a large number of numbers on its pages without substantial value-add, that can violate our guidelines, not to mention annoy users.
So, you’ll want to be careful if you add too many phone numbers for whatever purpose minus websites that specifically use it to help like Cutts says. So, you had better make a really good case if you plan on utilizing this to rank for phone numbers which is probably increasing in terms of finding contacts of phone numbers you don’t recognize.