HKIMO 2018 Grade 6 National Final (Heat) Set 03 Question 11

The eleven-digit number $\overline{20190513ABB}$ is divisible by 33, and $A\ne B$. Find the maximum of $A+B$.

Source glossary (English–Vietnamese): 11-digit number: số có 11 chữ số; Divisible by: chia hết; Maximum value: giá trị lớn nhất.