0671 is not a country code. Numbers inside a country start like this: Moldtelecom (Moldova), Bad Kreuznach (Germany), Cuttack, Odisha (India), Mayor Otano (Paraguay) and others. The first digit 0 is the trunk prefix for domestic calls and is dropped from abroad.
Have the full number? Check it in the number lookup.
| Area or operator | From abroad | Inside the country |
|---|---|---|
 Moldtelecom · Moldova | +373 671 … | 0671 … |
 Bad Kreuznach · Germany | +49 671 … | 0671 … |
 Cuttack, Odisha · India | +91 671 … | 0671 … |
 Mayor Otano · Paraguay | +595 671 … | 0671 … |
 Hoting · Sweden | +46 671 … | 0671 … |
 Yas · Tanzania | +255 671 … | 0671 … |
If a number starts with +, the first 1–3 digits are the country code. If it starts with 0 (8 in Russia and Kazakhstan), it is a domestic number: an area or operator code follows, and from abroad the 0 or 8 is replaced with + and the country code. The same digits can mean different places, so where the call came from matters.