By which I mean of course that today is November11l, 2011, abbreviated in many parts of the world as 11/11/11 and I have arranged for this to post at 11:11:11 am EST. That won't happen again for twelve whole hours, unless you keep military time in which case it will never happen again.

Some quick and dirty properties of Eleven: obviously, it is a prime number, the 5th smallest prime number. It is the smallest two-digit prime number in the decimal base; as well as, of course, in undecimal (where it is the smallest two-digit number). It is also the smallest three-digit prime in ternary, and the smallest four-digit prime in binary, (who knew?) but a single-digit prime in bases larger than eleven, such as duodecimal, hexadecimal, vigesimal and sexagesimal. 11 is the fourth Sophie Germain prime, the third safe prime, the fourth Lucas prime, the first repunit prime, and the second good prime. Although it is necessary for *n* to be prime for 2^{n} − 1 to be a Mersenne prime, the converse is not true: 2^{11} − 1 = 2047 which is 23 × 89. The next prime is 13, with which it comprises a twin prime. 11 is an Eisenstein prime with no imaginary part and real part of the form 3*n* − 1. Displayed on a calculator, 11 is a strobogrammatic prime and a dihedral prime because it reads the same whether the calculator is turned upside down or reflected on a mirror, or both.

Or, that's what Wikipedia tells me. For the moment, I'm giving it the benefit of the doubt.

George Takei on his FB status update said that it's "the one day when dyslexia has no power." One may also think of it as a pair of conjoined yet independent trilogies of prime numbers. I see the same prime number over and over again.

Happy 11:11:11 on 11/11/11! (See you in twelve hours. Or not.)

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