Sampat Kumar
Ansys Employee

Hi Vivekanandan, 
It's strange. I think this worked with every user who is not able to edit the number by double click. 
Have you tried double click on the number and entering the number, Although you will not be able to see the mouse cursor and the number when you enter, even after entering the number, press the Enter button, and you can see the number change. If this is not working, then try to do right-click on the number and click on Edit, then enter the number, then press the Enter button from the keyword, and the value will change. Please let me know if you did the same as I have mentioned above.
Which Ansys version are you using?