Iran , [ a ] [ b ] officially the Islamic Republic of Iran ( IRI ) [ c ] and also known as Persia , [ d ] is a country in West Asia . It borders Turkey to the northwest and Iraq to the west, Azerbaijan , Armenia , the Caspian Sea , and Turkmenistan to the north, Afghanistan to the east, Pakistan to the southeast, the Gulf of Oman and the Persian Gulf to the south. With a multi-ethnic population of about 86 million in an area of 1,648,195 km 2 (636,372 sq mi), Iran ranks 17th globally in both geographic size and population . [ 3 ] [ 8 ] It is the sixth-largest country entirely in Asia and one of the world's most mountainous countries. Officially an Islamic republic , Iran has a Muslim-majority population . The country is divided into fiv...
