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While trying to fill in credit card numbers into Excel 2010, when I write 4645890379859736 last number becomes 0

Example:4645890379859736 is turned into 4645890379859730

Note: I can't use any - or space

Please help me.

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That number is bigger than the biggest integer Excel can hold as a number.

Set the cell format to text before entering the number, or type an apostrophe at the start.

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Excel stores only 15 significant digits in a number, and changes digits after the fifteenth place to zeroes.

To work around this behavior, format the cell as text, then type the numbers. The cell can then display up to 1,024 characters.

Microsoft Support explained:

Excel follows the IEEE 754 specification on how to store and calculate floating-point numbers. Excel therefore stores only 15 significant digits in a number, and changes digits after the fifteenth place to zeroes.

If you type the number 1111222233334444 in a cell that uses the ####-####-####-#### format, Excel displays 1111-2222-3333-4440 in the cell. The actual number that you are attempting to store is 1,111,222,233,334,444, which is over one quadrillion. But because this number is so large, Excel drops the last (least significant) digit, and puts a zero in its place.

To add hyphen - or space , you simply type them.

If you type the number in the cell that is formatted as text, all the characters remain as you type them, because Excel does not attempt to store the credit card id as a number, but leaves it as text.

Instead of formatting as text, you can also begin the credit card number with apostrophe (link), so that it is interpreted as text.

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