In its entirety, that is not a valid country code.
What you may be looking for is the answer to puzzle 10 from God Tower (see related link.) You have to search each of the country codes separately so it works out like this:
255 = Tanzania
968 = Oman
977= Nepal
66 = Thailand
247 = Ascension
262 = Reunion Island
599 = Netherlands Antilles
The first letter of each country code gives you the answer "tontarn" which is the answer to the puzzle.
The country code and area code of Sonsorol, Palau is 680, 255.
The country code and area code of Penafiel, Portugal is 351, 255.
The country code and area code of Portuguesa, Venezuela is 58, (0)255.
The country code and area code of Arusha, Tanzania is 255, (0)27.
The country code and area code of Markazi, Iran is 98, (0)255.
The country code and area code of Coast, Tanzania is 255, (0)23.
The country code and area code of Tanzania, Tanzania is 255, (0)4.
The country code and area code of IJmuiden, Netherlands is 31, (0)255.
The country code and area code of Caras - Severin, Romania is 40, (0)255.
The country code and area code of Arai- Niigata, Japan is 81, (0)255.
The country code and area code of Dodoma and Iringa, Tanzania is 255, (0)26.
The country code and area code of Dar es Salaam, Tanzania is 255, (0)22.