Indonesia, officially the Republic of Indonesia (Indonesian: Republik Indonesia), is a country in Southeast Asia and Oceania. Indonesia comprises 13,466 islands and thirty three provinces. With over 238 million people, it is the world's fourth most populous country, and has the world's largest population of Muslims. Indonesia is a republic, with 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, Philippines, Australia, 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 eighteenth largest economy by nominal GDP and fifteenth largest by purchasing power parity.