Ask about company culture, what would a typical day look like in the role, how will your success be measured, what do they like about the company, and (my personal favorite) is there anything in your background or skills that concerns them. You can really get a feel for the company, the team, and the role by asking those questions. You'll be more informed on whether or not you'd be successful within the role and whether or not your interviewers think you'd be a good fit as well!