This happens because Excel formats the number in scientific notation, which is its default behavior for large numbers. To display the full number without scientific notation, you can follow the steps given below:
Select the cell or column.
Right-click and select Format Cells from the context menu.
3. In the Format Cells dialog box, choose the Number category.
4. Set the number of decimal places to 0 (if you don't need any decimals).
5. Click OK.
Now, it should be displayed in its full form, without scientific notation.