Telephone number is comprise of country code+area code+local number.
"City code" is another term for a telephone area code, especially in the context of a telephone number in international format.
It has the area code 082.
A telephone number is essentially your address within the telephone system. As with a postal address, it contains several layers of information. Your telephone number consists of a telephone country code, a city code or area code (in most, but not all, countries), and a subscriber number. You must dial the entire number, beginning with the country code, when calling from outside your own country, but you can usually dial only part of the number when calling locally or within your own country.
A telephone number is essentially your address within the telephone system. As with a postal address, it contains several layers of information. Your telephone number consists of a telephone country code, a city code or area code (in most, but not all, countries), and a subscriber number. You must dial the entire number, beginning with the country code, when calling from outside your own country, but you can usually dial only part of the number when calling locally or within your own country.
The telephone area code of your phone number.
The telephone exchange code is a numeric prefix in a telephone number that originally was used to identify the specific telephone switch that served that number. With number portability, the geographic zones are not as clear cut, but the exchange code still identifies the charging area. In North America (USA, Canada, etc.), the exchange code is the first three digits after the area code. In other countries, the length of the exchange code may vary.
Its the country code
Telephone country code +1 is North America (USA, Canada, etc.), but there is no area code 121 in North America. It is an invalid number.
00 + 1 + Area code + telephone number.
Telephone numbers in Turkey consist of the telephone country code +90, followed by a three-digit area code and a 7-digit subscriber number.
The 874 area code is an invalid unassigned number. If you are getting calls from this area code they are being "spoofed".