Where is telephone country code 880?

Country code +880 is Bangladesh. A number beginning with +880 50 is in a rural area near Bogra, including Dhunat, Shariakandi, Sibgonj, Dhupchachia, and Sherpur.

(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but North America (USA, Canada, etc.) uses 011, and many other countries use different prefixes.)