A five digit 3ab98 can be divided by 99 to find the five digit I really don't understand,

A five digit 3ab98 can be divided by 99 to find the five digit I really don't understand,

This number is 39798. Because the prime factor of 99 decomposition is 9 and 11, two conditions must be satisfied first: divisible by 11 and divisible by 9. The characteristic of a number divisible by 11 is to add the odd digit and even digit of a number from right to left, and then calculate their difference, if the difference is a multiple of 11 (...)