Pakistan is a federal parliamentary republic consisting of four provinces and four federal territories. It is an ethnically and linguistically diverse country, with a similar variation in its geography and wildlife. A regional and middle power, Pakistan has the seventh largest standing armed forces in the world and is also a nuclear power as well as a declared nuclear-weapons state, being the only nation in the Muslim world, and the second in South Asia, to have that status. It has a semi-industrialised economy with a well-integrated agriculture sector, its economy is the 26th largest in the world in terms of purchasing power and 45th largest in terms of nominal GDP and is also characterized among the emerging and growth-leading economies of the world