How to write 20-digits numbers without Excel automatically messing them up?

Hi,

Excel won't store numbers larger than 15 digits in a single cell.

All you can do is store larger 'numbers' as text strings but of course you can't do arithmetic with them.

You are being impacted by Excel's limits:
• Number precision 15 digits

What are your actual uses for the 20-digit "numbers"?
If they're some sort of identification or part number...use a number format of Text. Excel will not convert them to numbers.

Does that help?

The IEEE (Institute of Electrical and Electronic Engineers) established the double precision standard back in the '80's http://en.wikipedia.org/wiki/IEEE_floating_point so it is not really Microsoft's idea. Since there are very few problems that require better than double precision, higher precision has not caught on, yet. I see some references to a quad precision in some programming languages. If your problem needs that level of precision, you probably should consider performing this analysis in another language.

Can't comment on its efficiency or accuracy but there's an add in here http://precisioncalc.com/xlprecision.html which might be of interest.

Just as a matter of interest what are the very big numbers you're handling and what sort of arithmetic do you want to perform with them?

Originally Posted by Richard Buttrey

Can't comment on its efficiency or accuracy but there's an add in here http://precisioncalc.com/xlprecision.html which might be of interest.

Thanks but no, I don’t think refining the precision of my experiments is worth buying another software. Going up to 15-digits numbers already gave me a pretty good precision.

Originally Posted by Richard Buttrey

Just as a matter of interest what are the very big numbers you're handling and what sort of arithmetic do you want to perform with them?

Superior highly composite numbers: http://en.wikipedia.org/wiki/Superio...mposite_number

Deleted .

Originally Posted by Terminatrix

As for what I’m doing precisely with these numbers, it’s a secret that goes far beyond your imagination.

...and purely as a matter of interest again, why do you think such a rude remark is called for?

Are you always so superior to those who are genuinely trying to help or did you just get out of bed the wrong side? You might like to think on rule 6b if you continue to seek help in this forum. Others might have already given you an infraction. I'll wait to see if you care to mollify your comment.

Originally Posted by Terminatrix

Huh? What exactly would be rude in what I said? This must be a misunderstanding, I never intended to say anything insulting in my post.

I think I could give you the benefit of the doubt if you were not a native English speaker, although I cannot be certain of this just by knowing your location (France). The phrase "it’s a secret that goes far beyond your imagination" unfortunately implies that your imagination is superior to Richard's (or anyone else's in this thread). Maybe you didn't mean to imply this, but if you did, then it is a rather conceited thing to say, don't you think?

Pour améliorer la situation, je crois qu'il vaudrait mieux adapter ce que vous avez tapé ci-dessus (#7).

Originally Posted by Terminatrix

Huh? What exactly would be rude in what I said? This must be a misunderstanding, I never intended to say anything insulting in my post.

There was no misunderstanding on my part (nor it seems by others who have followed up).
If you're accepting that it was a misunderstanding on your part and assuming English is not your native language I'll accept that.

If however English is your language can I suggest you reflect a little more.

The OP does now appear to have reflected on the words used, as the offending statement has been edited out of post #7.

Google Translate is not very good at such subtleties.

Originally Posted by Terminatrix

Oh okay sorry, I thought it was some kind of expression to say that it would take a large amount of time to understand if you know what I mean.

OK fair enough. These things happen.
Take a positive from it in that in visiting a quite focused software forum you've acquired as a bonus a little more understanding of the pitfalls that lie in wait when subtleties of expression don't translate easily from one language to another.