Viber community is essentially a group chat, with a capacity of far more people than normal groups. It boasts a better admin control (such as having super admins instead of just admins, who can be promoted or demoted) as well as more chat features.
1. To remove someone as admin or superadmin, either select their avatar in the chat or go to Chat info and select their name.
2. Select “Remove as superadmin”. They will be demoted to admin.
3. In the case of an admin removal, you just have to select “Remove from chat” after following step one.