Write SQL query to solve given problem: What is the popularity of the professor who advises the highest number of students with the highest research ability?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT T2.popularity FROM RA AS T1 INNER JOIN prof AS T2 ON T1.prof_id = T2.prof_id GROUP BY T1.prof_id, T1.capability ORDER BY COUNT(T1.student_id) DESC, T1.capability DESC LIMIT 1