The International Mobile Equipment Identity (IMEI) is a unique 15-digit number that identifies a mobile phone. It is used by GSM networks to identify valid devices and can be used to track a phone if it is lost or stolen. The IMEI can also be used to check if a phone has been reported as lost or stolen.
In an emergency situation, it may be necessary to find the IMEI of a phone quickly. This can be done by dialing the emergency number 112 (or 911 in some countries) and then entering the following code: *#06#.