A nine digit number is formed from 1,2,3,4,5 such that product of all digits is always 1920. The total number of ways is  $393{(}^9{P}_r)$ , where the value of ‘r’ is ______

$$\begin{gathered} 1920=5\times 3\times 2^7=5\times 3\times 2\times 2\times 2\times 2\times 2\times 2\times 2=\frac{9!}{7!}=9\times 8 \\ 1920=5\times 3\times 4\times 2\times 2\times 2\times 2\times 2=\frac{9!}{7!}=9\times 8\times 7\times 6 \\ 1920=3,5,4,4,2,2,2,1,1 \\ =\frac{9!}{2!2!3!} \\ 1920= 3,5,4,4,4,2,1,1,1 \\ \frac{9!}{3!3!} \\ Total = \frac{9!}{5!}+\frac{9!}{2!2!3!}+\frac{9!}{3!3!}=\frac{9!}{7!}(1+42+210+140) \\ = 393{}^9{P}_2 \end{gathered}$$