Southeast Asia has an area of approximately 4,000,000 km2 (1.6 million square miles). As of 2013, Around 625 million people lived in the region, more than a fifth of them (143 million) on the Indonesian island of Java, the most densely populated large island in the world. Indonesia is the most populous country with 255 million people as of 2015, and also the 4th most populous country in the world. The distribution of the religions and people is diverse in Southeast Asia and varies by country. Some 30 million overseas Chinese also live in Southeast Asia, most prominently in Christmas Island, Indonesia, Malaysia, the Philippines, Singapore, and Thailand, and also, as the Hoa, in Vietnam.