# Mystical powers of the number 9 **URL:** \ **Category:** Factual Questions\ **Created:** [April 10, 2004, 12:55am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256 "2004-04-10T00:55:41Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![helieo](https://avatars.discourse-cdn.com/v4/letter/h/82dd89/32.png) [@helieo](https://boards.straightdope.com/u/helieo)\ **Post date:** [April 10, 2004, 12:55am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/1 "2004-04-10T00:55:41Z")
I remember reading a Newsweek article more than 10 years ago about the power of the number 9. I have not been able to get the article again from Newsweek online, so if anyone can help me locate it that would be great. In the meantime, remind me of all the strange/weird attributes that number has (and they were many…) ---
**Author:** ![Mathochist](https://avatars.discourse-cdn.com/v4/letter/m/c89c15/32.png) [@Mathochist](https://boards.straightdope.com/u/Mathochist)\ **Post date:** [April 10, 2004, 1:24am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/2 "2004-04-10T01:24:57Z")
> [@helieo](#): > > I remember reading a Newsweek article more than 10 years ago about the power of the number 9. I have not been able to get the article again from Newsweek online, so if anyone can help me locate it that would be great. In the meantime, remind me of all the strange/weird attributes that number has (and they were many…) “Mystical” is a _very_ strong word. If you’re talking about things like the divisibility rule (take the digit sum until you get a single digit, and that digit is the remainder on division by 9 or 9, if it’s evenly divisible), that sort of thing is a natural consequence of our numeration system. ---
**Author:** ![waterj2](https://avatars.discourse-cdn.com/v4/letter/w/858c86/32.png) [@waterj2](https://boards.straightdope.com/u/waterj2)\ **Post date:** [April 10, 2004, 1:55am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/3 "2004-04-10T01:55:15Z")
It was Ted Williams’s number, and he seemed to do all right with it. ---
**Author:** ![kniz](https://avatars.discourse-cdn.com/v4/letter/k/c37758/32.png) [@kniz](https://boards.straightdope.com/u/kniz)\ **Post date:** [April 10, 2004, 2:05am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/4 "2004-04-10T02:05:06Z")
> [@Mathochist](#): > > that sort of thing is a natural consequence of our numeration system. That does not mean that it is boring or not worth being aware of. :putz: ---
**Author:** ![David\_Simmons](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@David\_Simmons](https://boards.straightdope.com/u/David_Simmons)\ **Post date:** [April 10, 2004, 2:32am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/5 "2004-04-10T02:32:12Z")
I think you are talking about things like: Multiply 9 by any digit and the digits of the answer add up to 9. Like 2 X 9 = 18, 8 + 1 = 9. 3 X 9 = 27, 2 + 7 = 9 etc. But the same thing happens to the number that is one less than the base in any number system. For a base 9 system, 8 has the same properties as 9 does in a 10 base system. In an 8 base system it works for 7 etc. There are also some properties of 9 in arithmetic operations that I’ve forgotten. For example, something about “casting out nines” in multiplication. Or maybe it’s division. Someone is sure to be along shortly to clear it up. ---
**Author:** ![Bytegeist](https://avatars.discourse-cdn.com/v4/letter/b/9dc877/32.png) [@Bytegeist](https://boards.straightdope.com/u/Bytegeist)\ **Post date:** [April 10, 2004, 3:05am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/6 "2004-04-10T03:05:52Z")
[Google knows all.](http://www.jimloy.com/number/nines.htm) Don’t forget to [sing the song](http://www.school-house-rock.com/9.html) too. ---
**Author:** ![Tapioca\_Dextrin](https://avatars.discourse-cdn.com/v4/letter/t/3d9bf3/32.png) [@Tapioca\_Dextrin](https://boards.straightdope.com/u/Tapioca_Dextrin)\ **Post date:** [April 10, 2004, 3:16am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/7 "2004-04-10T03:16:03Z")
[This article](http://en.wikipedia.org/wiki/Number_9) should be a good place to start. ---
**Author:** ![Never\_to\_be\_Queen](https://avatars.discourse-cdn.com/v4/letter/n/e9c0ed/32.png) [@Never\_to\_be\_Queen](https://boards.straightdope.com/u/Never_to_be_Queen)\ **Post date:** [April 10, 2004, 3:22am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/8 "2004-04-10T03:22:44Z")
I know more about mysticism (from folklore, not practice) than I do about mathematics. Doing things three times is a very old and mystical practice. Perhaps the article told how doing things three time for three times would be extra sacred. ---
**Author:** ![ultrafilter](https://avatars.discourse-cdn.com/v4/letter/u/3d9bf3/32.png) [@ultrafilter](https://boards.straightdope.com/u/ultrafilter)\ **Post date:** [April 10, 2004, 4:58am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/9 "2004-04-10T04:58:16Z")
A lot of the wonderful properties of 9 are dependent on the fact that we use base 10. In base 16, 15 would have a lot of those properties. ---
**Author:** ![Mathochist](https://avatars.discourse-cdn.com/v4/letter/m/c89c15/32.png) [@Mathochist](https://boards.straightdope.com/u/Mathochist)\ **Post date:** [April 10, 2004, 5:20am UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/10 "2004-04-10T05:20:51Z")
> [@Never to be Queen](#): > > I know more about mysticism (from folklore, not practice) than I do about mathematics. Doing things three times is a very old and mystical practice. Perhaps the article told how doing things three time for three times would be extra sacred. Well, that’s rooted in numerology, which has close ties to basic music theory. Seven semitones from the tonal gives the fifth, which is one of the earliest harmonies. This has the connotations of “perfection”. Six semitones gives the augmented fourth: exactly half an octave. This dissonant tone was referred to as “the devil in music” and six has the connotations of “imperfection”. Three semitones gives the diminished third, which when added to the fifth and tonal gives a very full sounding chord. Accordingly, it has the connotations of “completion”. This sort of thing gives rise to “complete imperfection”, exemplified in the infamous 666 (three sixes). There’s more, but I get bored of this sort of thing quickly. ---
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [April 10, 2004, 1:23pm UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/11 "2004-04-10T13:23:01Z")
I heard that the currency of Burma/Myanmar, is based on units of 9.you hget 9 KYAT notes, 900 kyat notes etc. Has something to do with 9 being luckyn , I guess. ---
**Author:** ![Papermache\_Prince](https://avatars.discourse-cdn.com/v4/letter/p/f05b48/32.png) [@Papermache\_Prince](https://boards.straightdope.com/u/Papermache_Prince)\ **Post date:** [April 10, 2004, 1:49pm UTC](https://boards.straightdope.com/t/mystical-powers-of-the-number-9/239256/12 "2004-04-10T13:49:40Z")
> [@ralph124c](#): > > I heard that the currency of Burma/Myanmar, is based on units of 9.you hget 9 KYAT notes, 900 kyat notes etc. Has something to do with 9 being luckyn , I guess. It looks like you received bad information. From [www.Myanmar-travel.com](http://www.Myanmar-travel.com) [Currency](http://www.myanmar-travel.com/index.cfm?menuid=9) “Myanmar’s currency is the Kyat (pronounced “Chud”). There are bank notes of 1 Kyat, 5 Kyats, 10 Kyats, 15 Kyats, 45 Kyats, 90 Kyats and 200 Kyats. Officially the Kyat is divided up into 100 Pyas.”