The city has the postal code 34000 to 34990 . The area of the city is 47.84 sq mi (123.90 km 2 ) . The lowest elevation of Hanoi is 2 m  . Ravinder Bhalla (term ends December 31, 2021) is the mayor of Hanoi . The land area of the city is 314.95 sq mi (815.72 km 2 ) . The metro region has Population (2019): 2,700,000 population . 35°50′08″N 51°00′37″E﻿ / ﻿35.83556°N 51.01028°E are the coordinates of the city. . On February 17, 1909 the city was incorporated . The water area of the city is 21 km 2  (8 sq mi) . Hanoi is at an elevation of 0 meters . The highest elevation of Hanoi is 241.9 m (793.6 ft) . Hanoi is named for Christopher Columbus . The city Hanoi demonym is Catanesi . The density of  residents in  the metro region of Hanoi is 2,813/km 2  (7,290/sq mi) . 464.71/km 2  (1,203.6/sq mi) is the density of residents in  the urban region of Hanoi . 2,700/km 2  (7,000/sq mi) is the density of people in Hanoi . The area of the urban region is Area: 713 km2 (275 sq mi)
Official address of residents of the city Hanoi has zip code 34000 to 34990