Javascript is known to have 253 (9007199254740992, or 0x20000000000000) as the largest integer value for its Number object, as discussed here. I still don't understand why Number(0x20000000000000)+1 produces 0x20000000000000, but Number(0x20000000000000)+2 produces 0x20000000000002 (9007199254740994). Can someone please explain?
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2Read this [Article](http://en.wikipedia.org/wiki/Double_precision_floating-point_format) – Moritz Roessler Sep 17 '13 at 08:56
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Between 2^52=4,503,599,627,370,496 and 2^53=9,007,199,254,740,992 the representable numbers are exactly the integers. For the next range, from 2^53 to 2^54, everything is multiplied by 2, so the representable numbers are the even ones. – Moritz Roessler Sep 17 '13 at 08:59
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Thanks, that makes perfect sense. I'd accept it as an answer if you post it. – noseratio Sep 17 '13 at 09:05
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You're welcome =) I posted the quote as Answer – Moritz Roessler Sep 17 '13 at 09:18
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Quoted from this Wikipedia article
Between 2^52=4,503,599,627,370,496 and 2^53=9,007,199,254,740,992 the representable numbers are exactly the integers. For the next range, from 2^53 to 2^54, everything is multiplied by 2, so the representable numbers are the even ones.
Moritz Roessler
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