I need help with this and quick it's due tonight only question 9

Given a natural number, write a C ++ program that:
1. Displays the sum of even digits and the product of odd digits.
2. check if the first digit is equal to the last digit of n
3. construct the inverse formed only with odd numbers
4. calculate the number of digits 0 contained in n
5. check if n is a power of 10
6. Replace all even digits with an odd number 1 greater than it (next)
7. remove the odd digits from n
8. check that the number has all the digits equal
9. Displays the largest number that can be formed with the distinct digits that it has
contains n (eg for n = 25330727, 75320 will be obtained)