# Happy Palindrome Day! (Again!)

Aziz Inan explains this year's palindrome dates.

If you're mathematically minded enough, every day can be a special day — it's just that today's date, 11-02-2011, makes it more obvious for palindrome fans. Like Aziz Inan, for instance.

Inan, an engineering professor at the University of Portland, has made a study of dates that run the same numbers forward and backward. Several studies, in fact. Such combinations are considered numerical palindromes, much like the alphabetical palindromes that delight puzzle fans. (One of the most famous examples is the Garden of Eden's first introduction: "Madam, I'm Adam.")

This year has several date-based palindromes, depending on how you structure them: 1-10-2011, 1-11-11, 11-1-11 ... and if you go by the DD/MM/YYYY notation, Feb. 11 already marked 11-02-2011. Inan told the Los Angeles Times that today (or Feb. 11, if your calendar swings differently) is extra special because 11,022,011 equals another palindrome, 1001 X 11 X 1001.

Aziz Inan / Univ. of Portland

Aziz Inan, an engineering professor at the University of Portland, demonstrates the palindromosity of 11-02-2011 with a little help from a mirror image (and Cookie Monster).

"This is so much fun," Inan told the Times. "Engineering can get pretty boring because you talk about equations, but when I say, 'Do you know today is a special date?' it gets a lot of attention. It helps me change the subject for a few minutes and bring the students back from their dream or their hibernating."

Next year's Palindrome Days are Feb. 10 (2-10-2012), Feb. 21 (21-02-2012 in day/month/year) and Oct. 2 (2-10-2012 in day/month/year). Then there's 02-02-2020 — which is particularly notable not only because it's the next eight-digit palindrome date but also because it works whether you go with MM/DD/YYYY notation or DD/MM/YYYY.

But you don't have to wait all that long for the mother of all monodigital dates, which comes next week on Veterans Day. What will you be doing at 11:11 on 11-11-11? Going to the movies?

Correction for 3:35 p.m. ET: I originally wrote that Aziz's last name was "Anin," but the University of Portland pointed out that it's actually "Inan." Which is disappointing, because I was hoping he'd be the perfect palindromic match for Nina Ziza. The good news is that there's a Nani Ziza out there as well. I've also fixed another glitch: I originally referred to 11-02-2010 as Feb. 2 in day/month/year notation instead of the proper Feb. 11. Sorry about both those errors.

More calendrical fun:

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# Discuss this post

11-02-2011 is not Feb 2 in DD/MM/YYYY format. It is February 11th. Where's the editing?

• 1 vote
#1 - Wed Nov 2, 2011 2:39 PM EDT

#1.1 - Wed Nov 2, 2011 2:46 PM EDT

The editing was missing in this case and the brain was off ... sorry about that! Also, I turned Inan's name into an anagram ("Anin'). Fixed both those things, thanks for calling it to my attention.

• 1 vote
#1.2 - Wed Nov 2, 2011 3:28 PM EDT

try taking "la ruta natural" to Hyderabad

#2 - Wed Nov 2, 2011 3:00 PM EDT

rats live on no evil star.

#2.1 - Wed Nov 2, 2011 3:10 PM EDT

I always love when numerical palindromes show up in my job. Unfortunately my colleagues don't share my enthusiasm and find it strange that I'd even take notice of such things. And I never even told them about the times I look for them in the counter when I'm watching DVDs.

#3 - Wed Nov 2, 2011 3:05 PM EDT

@Bizzer: I have a strange affinity for prime numbers and sums of squares and cubes. Don't know why, just enjoy thinking about strange mathematical relationships, like the number "1729." It's remarkable, as a sum two different sets of cubes (9^3+10^3, 1^3+12^3).

#3.1 - Wed Nov 2, 2011 3:10 PM EDT

People are pointing out that it's not a real palindrom as "02" does not exist (as in 'I have 02 hands').

#4 - Wed Nov 2, 2011 3:17 PM EDT

Whoa whoa, just because a number doesn't make sense for one use doesn't mean it doesn't exist. Zero placeholders can be useful for plenty of applications, for instance 0500 for military time and such. I say, give the date full palindrome status. And then watch http://www.youtube.com/watch?v=Nej4xJe4Tdg.

#4.1 - Wed Nov 2, 2011 8:27 PM EDT

Ugh, palindrome. Sorry for the typo.

• 1 vote
#5 - Wed Nov 2, 2011 3:18 PM EDT

No problem. After having to correct two mistakes myself, I have no cause to gripe.

• 1 vote
#5.1 - Wed Nov 2, 2011 3:43 PM EDT

For the record, the term "Calendrome" was coined last year for these types of dates on UrbanDictionary.com.

#6 - Wed Nov 2, 2011 6:47 PM EDT

These phenomena are known as a "calendrome."

#7 - Wed Nov 2, 2011 6:53 PM EDT

Sorry for the repeat posts. Newbie!!

#8 - Wed Nov 2, 2011 9:13 PM EDT

I think the Palindrome is set in equation in the nature of physics, rather than in dates and numerical combinations. Since mathematics has changed over time, the truth of palendromes is set in something replicable but not changeable according to translation. I think it's a scientific theory that sets the location in earth time to predict variables in combination.

#9 - Fri Nov 4, 2011 12:15 AM EDT
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