The highest number in my collection is #53 (Star Dawn). However, his symphonies are largely a case of "If you've heard Juan, you've heard Amahl". I didn't want to paraphrase Stravinsky on Vivaldi: "He wrote one concerto, 600 times".
In any case, I have a large collection of Hovhaness's music. It's enjoyable, but very repetitive. My top 3 are Sym # 2 (Mysterious Mountain), Prayer of St Gregory, and a perfectly wonderful Prelude and Quadruple Fugue. Armenian with a Byzantine flavor.
As for Khachaturian, I'm also a big fan of his. His Gayne Ballet has more lively and tuneful music than any other ballet except Nutcracker IMO. Nutcracker has diversity. Gayne remains in Armenian territory, where it, nevertheless, manages wide variety. He was born in Tiflis, Georgia, by the way, of Armenian parents.