Nowadays, the MTN Simcards have become extremely cheap i.e. with just 100frs you can buy an MTN Simcard in the street.
Due to the fact that the MTN simcards have become very affordable, so many people often buy so many MTN Simcards and end up misplacing the casing; where the phone numbers of the MTN simcards are written.
If you forget the phone number of an MTN Simcard, just insert the unknown SIM card in to your phone and dial *123*5*4# and the phone number of that SIM card will show up on your screen. Copy your msisdn and store it in your phone book as MyNumber.
You can also dial *120# and you will also see the phone number of your SIM card.
Some people also check the phone number of a SIM card by sending a Bipme Message to a number they know, like their boyfriend or girlfriend,s number, and then copying the phone number from the Bipme message in the recipient,s phone.