Excel is excellent. No doubt about that. But excellence does not mean that, it will not have glitches. So Excel also have few !!!
Recently, We wrote a small data migration utility for our clients which reads data from Word file and store it in excel. The entries included Credit Card numbers which has 16 digits.
In all surprises, Excel was doing magic. When you enter a number greater than 15 digits, Excel rounds it off and you get zeros padding the end of your number.
Enter the number
234587654567123456 in Excel
and you get this
Excel supports 15 digits of precision in its cells. Credit card numbers are usually 16 digits.For identifying numbers, you should enter them as text. To enter a number as text, precede the entry with an dash (-) or format the cell as Text (Format>Cells>Number) before you enter the number.
Note : Tested and replicated in Excel 2007, Excel 2010