On this list of Chinese cities by population: https://en.wikipedia.org/wiki/List_of_cities_in_China_by_pop... #100 is https://en.wikipedia.org/wiki/Jiujiang with a total population of 4.6 million, of which 2.8 million live in urban areas and 1.1 million in the metropolitan area, i.e. the fact that cities often administratively subsume neighboring towns is already taken into account.