Answer:
34,584
Explanation:
For 3 to be a factor, the sum of digits must be a multiple of 3. That allows the missing digit to be 1, 4, 7.
For 4 to be a factor, the last two digits must be a number divisible by 4. That allows the missing digit to be 0, 4, 8.
The digit that makes the number have factors of both 3 and 4 is 4.