I'm having the exact same problem. My hubby's iPhone got the really long number and I get the 865-6696 at least 4 times a day 7 days a week. There has to be a way to find out who is behind it and get the number blocked.
"Unknown", "Restricted", and "Private Number" calls may not display correctly on UI during mobile terminated voice calls.
The following may be displayed: "7748283686237"
Sprint is currently aware of this and is investigating.
It is not a prank caller it is the corresponding numbers to private number it is actually someone calling who has their number marked private so instead of it saying "Private Number" the phone key number's that correspond with "Private Number" comes up instead.
It is always someone I know when it comes up I always let it go to voice mail and it is always the same couple of people that I know with a private number.
It seems to only happen with Private numbers they are ususally someone I know it just doesn't say private but has all of those numbers.
Sorry you are having this problem. The problem is the caller id is being spoofed by an application on the calling device.
With out the correct calling number we cannot block the service. We understand the frustration that this causes