The water area of the city is 4.12 sq mi (10.67 km 2 ) . Johannesburg is at an elevation of 6 m . The land area of the city is 1.275 sq mi (3.303 sq km ) . The density of  residents in  the urban region of Johannesburg is 2,305/km 2  (5,970/sq mi) . The city Johannesburg province is Kadiogo . Johannesburg has 19.500.000 population . The Johannesburg citys' lowest elevation is 1,750 m . This city is named after Calgary, Mull . On 1871 (Huntington) the city was incorporated . The demonym of the city Johannesburg is Mashhadi, Mashadi, Mashdi (informal) . Area : 993.5 km2 (383.6 sq mi) is the area of the urban region of Johannesburg . The highest elevation of Johannesburg is 424 m (1,391 ft) . The density of  residents in  the metro region of Johannesburg is 210.9/km 2  (546.2/sq mi) .  The city area code is 0211 . 56°19′37″N 44°00′27″E﻿ / ﻿56.32694°N 44.00750°E  are the coordinates of the city. . The mayor of Johannesburg is Armand Béouindé (since 2016) . Johannesburg is the government of Swedish Ice Hockey Association . The density of  inhabitents in Johannesburg is 7,400/km 2  (19,000/sq mi) . The postal code of the city is 080020 . Population: 3,113,725  is the population of the metro region of Johannesburg
There are more than 19502938 residents in Johannesburg