0542 is not a country code. Numbers inside a country start like this: Varansi, Uttar Pradesh (India), Balikpapan (Indonesia), Narowal (Pakistan), Nawalapitiya, Kandy (Sri Lanka). 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 |
|---|---|---|
 Varansi, Uttar Pradesh · India | +91 542 … | 0542 … |
 Balikpapan · Indonesia | +62 542 … | 0542 … |
 Narowal · Pakistan | +92 542 … | 0542 … |
 Nawalapitiya, Kandy · Sri Lanka | +94 542 … | 0542 … |
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.