Who is the richest man of Mumbai?

As of my knowledge cut off of 2021, Mukesh Ambani, the chairman and largest shareholder of Reliance Industries, is the richest man in Mumbai and India. He has a net worth of over $100 billion, making him one of the richest people in the world. Reliance Industries is a conglomerate with interests in areas such as petrochemicals, refining, oil and gas exploration, and retail. Ambani is also known for his philanthropic work and investments in new technologies such as 5G and AI. However, it's important to note that the net worth of individuals can fluctuate greatly, so this information may be subject to change.