Tonga, officially named the Kingdom of Tonga, is a Polynesian sovereign state and archipelago comprising 169 islands, of which 36 are inhabited. The total surface area is about 750 square kilometres (290 sq mi) scattered over 700,000 square kilometres (270,000 sq mi) of the southern Pacific Ocean. The state has a population of 100,651 people, of whom 70% reside on the main island of Tongatapu.