Excel data read using C#

Question

Excel data Reading using C#
but the value comes under formula

ex: A2 cell value 63
=Sum(54,9) =>63

This 63 value store one local variable using c#

What I have tried:

I'm using this one, the value comes -2141400 (Negative value coming)

Excel.Worksheet xlWorkSheet;
xlWorkSheet.Cells[1, 2].Value = -2141400

I want this xlWorkSheet.Cells[1, 2].Value = 63

can any one help us ?