Nigeria Business Directory: NGA is the ISO 3 alphabet country code of Nigeria. Currency of Nigeria is ₦, which has a short code of NGN. Capital of Nigeria is Abuja. Nigeria has the population of 195875237 and approximate area is 923768.00 square kilometers (or approx. 574029.4352 square miles). Population density of Nigeria is approx. 212/Km2 (or approx. 131.7368/mile2)