jmc

To get the constant term, the $\sqrt{x}$'s and $5/x$'s must cancel out. This occurs for the term with six $\sqrt{x}$'s and three $5/x$'s, so the coefficient is $$\left(\genfrac{}{}{0ex}{}{9}{3}\right)\cdot 5^3=84\cdot 125=\boxed{10500}.$$