Without using any file conversion software, I was able to format the phone numbers in excel without decimals i.e I was able to make the numbers display as phone numbers.
If you've got some phone numbers you would like to format in similar way, just follow me through the steps below:
==> Select range of cells containing the phone numbers
==> Right Click on the selection
==> Click format cells option
==> Click the "Numbers" tab
==> Click "Custom" in the category list
==> Click "O" as the type as seen in the screenshot below:
==> Click OK.
The numbers in the selected range of cells should now display the phone numbers completely.
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