-21
There are 5460 five digit numbers with a digit sum of 22.
450.
What is the units digit of the least whole number greater than 1000 whose digits are all different?
69
There are 15 of them.
There are 6 such numbers.
Two-digit prime numbers whose digits add up to 10 are:193773
1348.
-1
73 satisfies your condition.
Smallest is 11 & Largest is 77.