If you have newer version of Xilinx,you can use numeric_std package & use '/' operator. The division operator is recognized by ieee.numeric_std.I am not sure if you can use this package with older versions of Xilinx.
numeric_std is valid only if your inputs are of datatypes UNSIGNED/SIGNED/NATURAL/ INTEGER.
With the old synopsys libraries, division is however suppported for integer datatype, so maybe you can conversions if that is simple for you.
Thanks for your reply. I am using older version of xilinx. I need to do use a number like 2500000 for division. This number exceeds integer range. How can I use division for this number without initializing it as integer?