Just for fun, I&#x27;ve tried that with the OSX calculator (in El Capitan, in case that matters).<p>When I paste the number in the article (17281580835365214242) into it, it shows as 9223372036854775807. Typing it by hand does the same, when you enter the last digit it transforms into that number, which is 0x7FFFFFFFFFFFFFFF in hex.<p>Funnily enough, if I paste the hex value (EFD4823541245822) and transform it to dec, it shows as the correct number, the one you can&#x27;t paste or type.<p>So, the OSX calc looks broken too, in an even weirder way.<p>edit: Forgot to mention this was in programmer&#x27;s view. As far as I can tell, other modes work fine.