What does Sami mean?
From the root s-m-w (س-م-و, 'to be high, elevated'), meaning 'elevated, lofty, sublime, eminent'. Note the distinct name Sami' (سميع, 'all-hearing'), which comes from a different root (s-m-'); the two are easily confused in transliteration.
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.