There is no telephone country code +77, as such, but +7 (dialed as 00 7 from many places) is Russia and Kazakhstan, and all numbers beginning with +7 7 are allocated to Kazakhstan. However, it is incorrect to refer to "country code +77"; the correct country code is just +7.
All numbers in Kazakhstan begin with +7 7.
Landlines in Kazakhstan begin with +7 71 or +7 72.
Mobiles in Kazakhstan begin with +7 70 or +7 77.
Other services in Kazakhstan begin with +7 75 or +7 76.
Numbers beginning with +7 73, +7 74, +7 78, and +7 79 are invalid codes.
(Originally, country code +7 was the entire USSR, but all the other former Soviet republics split off into their own individual country codes.)
(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.)
All international codes starting with a 7 - belong to either the Russian federation, or Kazakhstan.
The country code and area code of Kairouan, Tunisia is 216, 77.
The country code and area code of Shiga, Japan is 81, (0)77.
The country code and area code of Lumbini, Nepal is 977, (0)77.
The country code and area code of Venlo, Netherlands is 31, (0)77.
The country code and area code of Bauchi, Nigeria is 234, (0)77.
The country code and area code of Opole, Poland is 48, (0)77.
The country code and area code of Kiskunhalas, Hungary is 36, (06)77.
The country code and area code of Batam, Indonesia is 62, (0)77.
Country code +94 is Sri Lanka; +94 77 is a mobile number.
The country code and area code of Surat Thani, Thailand is 66, (0)77.
+44 is the country code for the United Kingdom +44 77 is a mobile phone.
The country code and area code of Ilocos Sur, Philippines is 63, (0)77.