7
95
All nonzero numbers have factors. Some factors are odd numbers. The largest of these would be the greatest odd factor. Of course, the greatest odd factor of any odd number is the number itself.
15
I would call an odd number factor a factor that is an odd number. I would call a number with an odd number of factors a perfect square.
The largest odd factor of 2011 is 2011.
The question does not make any sense at all because72 is not an odd number72 is not the largest factor of 720
501
9
365
15
7
95
81 is.
17
215
All nonzero numbers have factors. Some factors are odd numbers. The largest of these would be the greatest odd factor. Of course, the greatest odd factor of any odd number is the number itself.