the nicobar islands include 22 islands of different sizes. the largest one is great nicobar. the total land area of the chain is 1841 km². the highest point on the nicobars is mount thullier at 642 m. the population of the islands was 42,026 in 2001, roughly 65% of whom are indigenous peoples (the nicobarese and shompen peoples, listed among the scheduled tribes of india), and 35% migrants from india and sri lanka.