Jane said:
I need to type numbers that have 16 digits. Excel drops all
digits after 15.
More accurately: it turns them into zero(!).
My format is set to Number with 0 decimal places, but I
have also tried a custom format with 16 zeros.
How can I make that 16th digit hold?
If you want the 16-digit string to be treated as a number,
I believe the answer is "you cannot".
If you simply want to enter a 16-digit string as text, you can
prefix it with a single quote (apostrophe). For example:
'12345678901234567890.
If you need to enter a number with more than 15 significant
digits, you can enter the first 15 digits using scientific notation.
For example: 123456789012345e2. But you still lose the
16th and more digits.
The problem is: internally, Excel uses a standard binary
representation of numbers that is accurate to only 15 decimal
digits. Excel could format a 16th digit, but it would be wrong
in most cases. Anything beyond that is pure fantasy.