There are 17,508 islands in Indonesia, of which only about 6,000 are inhabited. The largest and most well-known islands are Sumatra, Java, Borneo (shared with Malaysia and Brunei), Sulawesi, and New Guinea (shared with Papua New Guinea). These islands are all quite large; Sumatra is the sixth largest island in the world, Java is the tenth largest, Borneo is the third largest, Sulawesi is the eleventh largest, and New Guinea is the second largest.