The number of 5-digit natural numbers, such that the product of their digits is 36, is ____

$$\begin{gathered} 36=2^2\cdot 3^2\cdot 1 \\ \text{ Five-digit combinations can be } \\ \left\{ (1,2,2,3,3)(1,4,3,3,1)\left(\right(1,9,2,2,1) (1,4,9,11\left)\right(1,2,3,6,1\left)\right(1,6,6,1,1)\right\} \\ \mathrm{The} \mathrm{number} \mathrm{of} 5 \mathrm{digit} \mathrm{numbers} = \\ 3\times \frac{{\displaystyle 5!}}{{\displaystyle 2!2!}}+\frac{{\displaystyle 5!}}{{\displaystyle 3!\times 2!}}+\frac{{\displaystyle 5!}}{{\displaystyle 2!}}+\frac{{\displaystyle 5!}}{{\displaystyle 3!}}==(30\times 3)+10+60+20=180 \end{gathered}$$