Iran's total population is large, at a 77.2 million. Its population density is 122 people per square mile. It has a growth rate of 1.05%. Iran is growing pretty fast. More people are leaving the country than coming in to the country. They five largest cities in the countries are Tehran,Mashhad,Isfahan,Karaj andTabris. Iran is mostly urban. The fight against Isis is fairly near them. That could be why people are leaving. The number of people leaving is .08. The fertility rate is 1.85. The world rank is 162nd place for population density. The world rank for population is 17th place.