There are many paid services that allow members to do a Reverse Phone Scan and find out who owns a certain phone number. These databases include cell phone, VoIP and unlisted numbers, and are often include millions of entries.
So… what is the likelyhood that YOUR number would be in these databases?
If you live in America, then the odds are overwhelming that your details will be in the database. These services have practically every number in America. However, if you are in any other country, you probably won’t find your number in these databases.
If you are concerned about your details being accessible to anyone who pays a small fee, you can usually request for your information to be taken out.