MSISDN is a number uniquely identifying a subscription in a GSM or a UMTS mobile network. Simply put, it is the telephone number of the SIM card in a mobile/cellular phone. This abbreviation has several interpretations, the most common one being "Mobile Subscriber Integrated Services Digital Network Number". An MSISDN is limited to 15 digits, prefixes not included.
In GSM(The Global System for Mobile Communications) and its variant DCS 1800, MSISDN is built up as
MSISDN = CC + NDC + SN CC = Country Code NDC = National Destination Code, identifies one or part of a PLMN (Public land mobile network)
SN = Subscriber Number
In the GSM variant PCS 1900, MSISDN is built up as
MSISDN = CC + NPA + SN CC = Country Code NPA = Number Planning Area SN = Subscriber Number
NOTE: If *1# is not working then call *#1#