2 ]  ( 4th ) (2010 [update] ) • 27,462 /km 2 (71,126 /sq mi) • 15,644,040 [ 3 ]  ( 3rd ) (2010 [update] ) Spoken languages   [show] Bengali English Hindi [ 4 ] Ethnic groups     [show] Hindu Muslim Christian Jain Time zone IST ( UTC+5:30 ) Area • Elevation 1,480 km 2 (571 sq mi)