Singapore Business Directory: SGP is the ISO 3 alphabet country code of Singapore. Currency of Singapore is $, which has a short code of SGD. Capital of Singapore is Singapore. Singapore has the population of 5791901 and approximate area is 697.00 square kilometers (or approx. 433.1158 square miles). Population density of Singapore is approx. 8309/Km2 (or approx. 5163.2126/mile2)