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While entering the number like 999999994000000000000000000 into the number format applied cells (Formats like Number, Currency, Accounting and other number related custom formats) in Spreadsheet. Our Spreadsheet will display the value as 9.99999994e+26.
In MS Excel, the full number is displaying with the format applied in it. Below mentioned the screenshot for reference,

We need to provide the support to display the large number as it is like MS Excel without converting it as a scientific notation.