Maimūn
Maimūn is Arabic in origin, from the root m-y-m-n which relates to blessing, rightness, and good fortune; it is also attested in Persianate and Malay records.
No. Maimūn is not a Qur'anic proper name; it is a lexical adjective used historically as a given name.
Yes. The name occurs historically in Persianate and Malay usage and in other parts of the Muslim world as a rare male personal name.
Common transliteration variants include Maimun, Maymun, and Maimoon; pronunciation and spelling vary by language and region.
Yes. The name literally connotes blessing, good fortune, and auspiciousness and has been chosen historically for those meanings.