'00' is not part of the country code, it is a commonly used international access prefix. Country code +62 is Indonesia, and +62 819 is an XL Postpaid mobile.
The telephone country code for Indonesia is +62. Replace the plus sign with your international access prefix (for example, 00).
00 isn't part of the country code, it is a commonly used international access prefix. Assuming that 00 is your access prefix, you are thus asking about telephone country code +62, which is Indonesia, and telephone area code +62 857, which is a mobile phone served by IM3.(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, Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)
This sort code belongs to Halifax. The code is assigned to the Blackburn branch.
The country code and area code of Jember, Indonesia is 62, (0)33.
The country code and area code of Bogor, Indonesia is 62, (0)25.
The country code and area code of Kunarha, Afghanistan is 93, (0)62.
The country code and area code of Arobaya, Indonesia is 62, (0)31.
The country code and area code of Bandung, Indonesia is 62, (0)22.
The country code and area code of Cirebon, Indonesia is 62, (0)23.
The country code and area code of Ende, Indonesia is 62, (0)38.
The country code and area code of Jombang, Indonesia is 62, (0)32.
The country code and area code of Kupang, Indonesia is 62, (0)39.