Asia has the largest number of people exposed to natural disasters, but African countries are the most vulnerable to them, largely because of political instability, corruption, poverty and inequality, a new global assessment shows.

India has a billion people at risk, with China, Bangladesh, Indonesia, the Philippines, Japan and Pakistan also ranked among the 10 countries with the most people exposed to natural hazards, according to data compiled by the U.K.-based risk management company Verisk Maplecroft.

It said Japan's population is the eighth-most-acutely exposed to natural hazards, with 122 million people — 96 percent of the population — at risk from tsunami, earthquakes or typhoons.