Indonesia is a sovereign state in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 17,508 islands. It encompasses 33 provinces and 1 Special Administrative Region ( by a pre-colonial monarchy) with over 238 million people, making it the world's fourth most populous country. Indonesia's republic form of government comprises an elected legislature and president. The nation's capital city is Jakarta. The country shares land borders with Papua New Guinea, East Timor, and Malaysia. Other neighboring countries include Singapore, the Philippines, Australia, Palau, and the Indian territory of the Andaman and Nicobar Islands. Indonesia is a founding member of ASEAN and a member of the G-20 major economies. The Indonesian economy is the world's 16th largest by nominal GDP.