Indonesia is the world's fourth-most populous country and the most populous Muslim-majority country. Java, the world's most populous island, is home to more than half of the country's population. The country's capital, Jakarta, is the world's second-most populous urban area. Indonesia shares land borders with Papua New Guinea, East Timor, and the eastern part of Malaysia, as well as maritime borders with Singapore, Vietnam, Thailand, the Philippines, Australia, Palau, and India (Andaman and Nicobar Islands). Despite its large population and densely populated regions, Indonesia has vast areas of wilderness that support one of the world's highest levels of biodiversity.