List out all of the factors to 32.
1, 2, 4, 8, 16, 32
From the list, we either have 4 or 16 as our number.
Prime factorisation for 4 is 2 x 2 and prime factorisation for 16 is 2 x 2 x 2 x 2
Thus, that doesn't help our case.
Looking at our requirement: the sum of its digits is odd.
Well, 4 can be rewritten as 0 4 and its sum is even.
The sum for 1 + 6 is obviously odd, which means that 16 is the number.