Nigeria, officially the Federal Republic of Nigeria, is a country in West Africa, bordering Niger in the north, Chad in the northeast, Cameroon in the east, and Benin in the west. Its coast in the south is located on the Gulf of Guinea in the Atlantic Ocean. The federation comprises 36 states and 1 Federal Capital Territory, where the capital, Abuja, is located. The constitution defines Nigeria as a democratic secular state. Nigeria has been home to a number of ancient and indigenous kingdoms and states over the millennia. With 206 million inhabitants, Nigeria is the most populous country in Africa. Nigeria is viewed as a multinational state as it is inhabited by over 250 ethnic groups, of which the three largest are the Hausa, Igbo and Yoruba. The official language of Nigeria is English, chosen to facilitate linguistic unity at the national level. Nigeria is divided roughly in half between Christians, who live mostly in the southern part of the country, and Muslims, who live mostly in the north. A minority of the population practice religions indigenous to Nigeria, such as those native to the Igbo and Yoruba ethnicities.