Where is the highest human habitation place on earth?

The answer depends on the area of the city. Shanghai's area is 2605 square kilometers with 6845 people per square kilometer and is ranked first

Mumbai's area is 603 square kilometers with 12,5 million people, the denisity here is 20,694 per square kilometer

Seoul has over 17,000 people per square kilometer

Ahmedabad Municipal Corporation boasts 27,307 per square kilometer