What does Hadi mean?
From the root h-d-y (ه-د-ي, 'to guide, to lead rightly'), meaning 'guide, leader, one who directs to the right path'. Al-Hadi is also one of the names of God; as an everyday human given name it is common and is presented here in that sense.
What does Sultan mean?
From Arabic 'sultan', originally an abstract noun meaning 'strength, authority, rulership' (from 'sulta', power/authority), later a sovereign's title. Note: 'ruler/authority', and distinct from 'malik' (king) proper.