The city land area is 11,609.91 km 2  (4,482.61 sq mi) . Hanoi is the government of National Park Service . The city has the postal code 130000 . The urban region is 14.0 sq mi (36 km 2 ) in area . The city was incorporated in March 6, 1836 (city) . 2,813/km 2  (7,290/sq mi) is the density of inhabitents in  the metro region of Hanoi .  The city area code is +374 10 . Hanoi is named for Confluence of Grand River and Gunnison River . The Hanoi citys' lowest elevation is 190 m  . 5,300/km 2  (14,000/sq mi) is the density of people in Hanoi . Hanoi is at an elevation of 2250 m . Populations (2019): 3,731,447 is the population of the metro region of Hanoi . The density of  inhabitents in  the urban region of Hanoi is 4,800/km 2  (12,000/sq mi) . 385.8 sq mi (999.3 sq km ) is the area of the city namedHanoi . The city Hanoi demonym is Barranquillero/a . Tang Liangzhi is the mayor of Hanoi . The city water area is 4.46 sq km  (1.72 sq mi)
There is more land area than water covered area in Hanoi