My personal preference would be: 100000 (monetary symbol), but, I also understand that others might prefer the symbol before the numeric (i.e. $100000), even though you would not say "Dollars one hundred thousand" in English.
The closest you get to an international standard (that not many use) is the International Bureau of Weights and Measures recommending (ideally thin) spaces (so "10 000")
Interesting! Do you know of any countries that use the underscore? I believe I've seen France(...?) use spaces as a separator, but I've never come across the underscore.
Personally I would like some means of breaking up units of triplets that could be used universally. It's frustrating that there isn't a standard across the globe for such crucial means of expression. It wasn't until fairly recently that I learned that the comma wasn't the universal standard.
I am not aware of any country using the underscore to separate multiple of thousands, I just thought of it because it can be used for that purpose in some programming languages. Ans if it's true that no country is using it, then I guess it could be used as a 'neutral' way of doing it.
Spaces cause ambiguity with separate values like 123 456. Underscores are ambiguous with missing values due to the common use of a line segment to indicate where to fill out form values in addition to the same separate values issue as spaces.
Bahraini Dinar (and some other Dinars I believe) use 3 digits for their currency. I wouldn't assume no dollar does it. Sure, it's very unlikely. But if you've never dealt with some other currency, it may not by that obvious.
Prior to the decimalization of the stock market, I'd see $42.0625 and similar prices. 0.0625 being 1/16th of a dollar.
Post 2001, the requirements are that that stocks traded for under $1.00 may have a minimum spread of $0.0001 and so you still can see it and have to work with it.
It took me a minute. My brain saw the period and then truncated the third zero to make sense of it. This is pretty common in humans. But because I thought that one hundred dollars was odd, I read the article, which I then realized it was one hundred thousand.
Cent is short for 'centime' or 1/100th, so indeed, nobody is using three digits to represent cents. But there are currencies with finer grained denominations than cents.