Eleven

Properties

11 is prime.

For different bases

1. 11 is strictly non-palindromic, meaning it's never a palindrome in bases from binary to the base one below it (base 10).
2. In binary, 11 is 1011.
3. In ternary, 11 is 102.
4. In quaternary, 11 is 23.
5. In quinary, 11 is 21.
6. In seximal, 11 is 15.
7. In septimal, 11 is 14.
8. In octal, 11 is 13.
9. In nonary, 11 is 12.
10. In decimal, 11.
11. In elevenary, 11 is 10.
12. In higher bases, 11 gets its own symbol, usually 'B'.
13. In negabinary, 11 is 11111
    and -11 is 110101.
14. In negaternary, 11 is 102
    and -11 is 1211.
15. In negaquaternary, 11 is 123
    and -11 is 31.
16. In negaquinary, 11 is 131
    and -11 is 34.
17. In negaseximal, 11 is 155
    and -11 is 21.
18. In negaseptimal, 11 is 164
    and -11 is 23.
19. In negoctal, 11 is 173
    and -11 is 25.
20. In neganonary, 11 is 182
    and -11 is 27.
21. In negadecimal, 11 is 191
    and -11 is 29.
22. In negelevenary, 11 is 1X0
    and -11 is 10.