Excel only provides for 15 significant digits as a floating point number.
Which is a lot more accuracy than is needed for most fields of science,
certainly sufficient rocket science.. .

If you want a "number" with 16 characters, it is very unlikely that you
should ever have considered it to be a number (to be used arithmetically),
but rather it is an identification "number" and should have been
formatted as text.

This *problem* usually crops up when people enter Credit Card Numbers
into Excel and end up with invalid numbers, as most credit cards are 16
digits.
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HTH,
David McRitchie, Microsoft MVP - Excel [site changed Nov. 2001]
My Excel Pages: http://www.mvps.org/dmcritchie/excel/excel.htm
Search Page: http://www.mvps.org/dmcritchie/excel/search.htm

"STLKU" wrote in message ...
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