If you need to do math with these numbers, you'll have to find a
workaround - XL only retains 15 decimal digits of precision.

If it's a part number or some other number that you won't do math on,
preformat the cell as Text, or prefix the number with an apostrophe (').

In article ,
"Andre" wrote:

I need to enter more than 10 numbers to left of the decimal and more than 5
to the right of the decimal. Right now if I enter more than 10 numbers to the
left of the decimal, the number to the right of will start to round
automatically.