What does the 'halo' around the painted person's head depict?

His divinity

Answer:  His divinity
A halo is seen around Sultan Abdullah Qutb Shah's head, which depicts his divinity.

An important portrait of Sultan Abdullah Qutb Shah of Bijapur is in the collection of National Museum, New Delhi, India. There is an inscription on the top in Persian. Sultan Abdullah Qutb Shah was an able ruler of the famous Deccani state of Bijapur, which attracted scholars and artists from various parts of the world. Here, he is enthroned and we can see him holding the sword in one hand, symbolising his political sovereignty. Besides, a halo is seen around his head, which depicts his divinity.