Out of these, 5.34 lakh people were identified as high-risk contacts, the Brihanmumbai Municipal Corporation (BMC) said.
So far, 13.28 lakh people have completed their 14-day quarantine.
As of now, 2.46 lakh people are under home quarantine and 14,288 under institutional quarantine, the BMC said on its website.
Out of 14,288 people under institutional quarantine, 11,409 are lodged at 328 CCC-1 (COVID care centre) facilities, which have a collective capacity of over 50,000 beds, while 2,879 are kept at 57 CCC-2 facilities, having more than 6,100 beds, the BMC said.
The CCC-1 facilities are set up mostly in hotels and halls and do not have 24-hour monitoring facility, while CCC-2 are government facilities where doctors and nurses are available round-the-clock.
The BMC said it has acquired several hotels, guest houses, gymkhanas, halls and other places for institutional quarantine and isolation purposes.
It has sealed 6,552 buildings and declared 750 slums and chawls (small tenements) as containment zones, after one or more persons there tested positive for coronavirus.
Till Monday, Mumbai reported 85,326 COVID-19 cases and 4,935 deaths due to the disease, the BMC said.