How to convert a number(Integer) into years,months,days format in oracle Select query?

For example: I have a select query which i will get no. of non null records on a column x. Let it be count(x) = 35. As per my requirement i need to display the value as 1m,5d. If 369 days then 1y4d(Here actually i am leaving .25 days but if possible should not neglect. Also should consider leap year situations) If 400 days then 1y1m5d (same rule appliable as above) Please let me know if you have a solution. Thanks in advance.