Complete the sequence:
9, 72, 243, 576, _______

Let's analyze the mathematical pattern of the sequence by factoring out 9 from each term:
* 1st term: $9=9\times 1=9\times 1^3$
* 2nd term: $72=9\times 8=9\times 2^3$
* 3rd term: $243=9\times 27=9\times 3^3$
* 4th term: $576=9\times 64=9\times 4^3$

Following the logic of $9\times n^3$, the 5th term must be:

$$9\times 5^3=9\times 125=1125$$