JT

Did you try keying in your cell phone number? Is it listed in your local white pages? This could be a problem unless you want a bunch of telemarketers calling your cell phone.

Google may be accessing the database of listed phone numbers or they may be aggragating from many sources which would include both listed and unlisted numbers.

When I was acting as a security expert consulting victims of stalkers, I always adviced them against getting an unlisted number. The unlisted numbers were still in the phone company database and were often accessed by employees and even sold in bulk to other vendors. Instead, I advised them to list the number under a fictious name like "Clark Kent" or "Jimmy Olsen"