What is the largest residential royal palace in the world?

The Istana Nurul Iman is the official residence of the Sultan of Brunei, Hassanal Bolkiah, and the seat of the Brunei government. Upon completion, Istana Nurul Iman became the largest residential palace in the world and the largest single-family residence ever built. The palace contains 1,788 rooms, which includes 257 bathrooms, a banquet hall that can be expanded to accommodate up to 5,000 guests, a mosque accommodating 1,500 people. Istana Nurul Iman contains 2,152,782 square feet (200,000 m²) of floorspace.