$$n^a \times n^b=n^{a+b}$$
So $${{\mathtt{5}}}^{{\mathtt{3}}}{\mathtt{\,\times\,}}{\mathtt{5}}{\mathtt{\,\times\,}}{{\mathtt{5}}}^{{\mathtt{4}}}{\mathtt{\,\times\,}}{{\mathtt{5}}}^{{\mathtt{2}}} = {{\mathtt{5}}}^{{\mathtt{3}}}{\mathtt{\,\times\,}}{{\mathtt{5}}}^{{\mathtt{1}}}{\mathtt{\,\times\,}}{{\mathtt{5}}}^{{\mathtt{4}}}{\mathtt{\,\times\,}}{{\mathtt{5}}}^{{\mathtt{2}}} = {{\mathtt{5}}}^{\left({\mathtt{3}}{\mathtt{\,\small\textbf+\,}}{\mathtt{1}}{\mathtt{\,\small\textbf+\,}}{\mathtt{4}}{\mathtt{\,\small\textbf+\,}}{\mathtt{2}}\right)} = {{\mathtt{5}}}^{{\mathtt{10}}} = {\mathtt{9\,765\,625}}$$
.