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