Why does my phone have a mobile identification number all of a sudden
In what regards is this affecting your service/phone?
"The mobile identification number (MIN) or mobile subscription identification number (MSIN) refers to the 10-digit unique number that a wireless carrier uses to identify a mobile phone, which is the last part of the international mobile subscriber identity (IMSI)."
Phones have always had one. They don't always match your phone number though.