861 is not a country code. Numbers inside a country start like this: TM-Cell (Turkmenistan). The first digit 8 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 |
|---|---|---|
 TM-Cell · Turkmenistan | +993 61 … | 861 … |
| Area or operator | From abroad | Inside the country |
|---|---|---|
 Krasnodar Territory · Russia | +7 861 … | 8861 … |
 Traunstein · Germany | +49 861 … | 0861 … |
 Nellore, Andhra Pradesh · India | +91 861 … | 0861 … |
 Maliq, Korçë · Albania | +355 861 … | 0861 … |
 Maulavibazar/Rajnagar · Bangladesh | +880 861 … | 0861 … |
 Vodacom · Congo - Kinshasa | +243 861 … | 0861 … |
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.