That is a big possibility. However, since the Lord has not told us this is Satan, we gain nothing by insisting that he is. The important thing is not his precise identity (beyond what the Spirit has revealed), but instead that this king over the hordes of the bottomless pit must do the will of God.
11 They have as king over them the angel of the bottomless pit. His name in Hebrew is Abaddon, and in Greek he is called Apollyon.