Why is Russia called Rusastan in Armenian?

[RussiaPrussia]

Why is Russia called Rusastan in Armenian? Same like your country it ends with stan just like other stan countries in central asia.

[Methmatician]

I think 'stan' means something like "land" in Armenian. So I'm guessing "Rusastan" means "Land of Rus". Just a theory.

[Útrám]

The ending suffix "-stan" means "place of"

[Musso]

The name for armenia in armenian is 'hayastan'. We often used the 'stan' prefix to denote a country, as in 'land of Russians', and so forth. I believe this is an old Persian/Indo-European influence.

[Arsen_]

-ստան (-stan)

Forming nouns with the meaning of place, especially country names.

Հայաստան (Hayastan) — Armenia
Վրաստան (Vrastan) — Georgia

Etymology
Persian ستان (stān) and Sanskrit स्थान (sthā́na), both deriving from common Indo-Iranian verbal stem √sthā ("to stand, stay"), from Proto-Indo-European *steh₂- (“to stand”), whence also English verbs stay and stand.

Also for example in Armenian
Poland = Lehastan
Persia = Parskastan
Turkey = Tachkastan (from word Tachik = Turk) etc

But "stan" came in Middle ages.
In Ancient Classical Armenian for naming countries was used just plural form like bellow:
Hayk = Armenia (literally Armenians)
Virk = Georgia (literally Georgians)
Aghvank = Albania (literally Albanians) etc