0172 is not a country code. Numbers inside a country start like this: Vodafone (Germany), China Mobile (China), Chandigarh, Punjab (India), Alphen Aan den Rijn (Netherlands) 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 |
|---|---|---|
 Vodafone · Germany | +49 172 … | 0172 … |
 China Mobile · China | +86 172 … | 0172 … |
 Chandigarh, Punjab · India | +91 172 … | 0172 … |
 Alphen Aan den Rijn · Netherlands | +31 172 … | 0172 … |
 Hirosaki, Aomori · Japan | +81 172 … | 0172 … |
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.