Seventeen

A friend's favorite number.

Properties

17 is prime. 2^17-1 = 131071, which is prime, therefore (2^17-1)(2^16) = 8,589,869,056, which is a perfect number.

For other bases

1. In binary, 17 is 10001, a palindrome!
2. In ternary, 17 is 122.
3. In quaternary, 17 is 101, another palindrome!
4. In quinary, 17 is 32.
5. In seximal, 17 is 25.
6. In septimal, 17 is 23.
7. In octal, 17 is 21.
8. In nonary, 17 is 18.
9. In decimal, 17.
10. In elevenary, 17 is 16.
11. In dozenal, 17 is 15.
12. In baker's dozenal, 17 is 14.
13. In biseptimal, 17 is 13.
14. In triquinary, 17 is 12.
15. In hex, 17 is 11.
16. In suboptimal, 17 is 10.
17. In negabinary, 17 is 10001, just like binary,
    and -17 is 110011.
18. In negaternary, 17 is 212
    and -17 is 1101.
19. In negaquaternary, 17 is 101, just like quaternary,
    and -17 is 1313.
20. In negaquinary, 17 is 122
    and -17 is 43.
21. In negaseximal, 17 is 145
    and -17 is 31.
22. In negaseptimal, 17 is 153
    and -17 is 34.
23. In negoctal, 17 is 161
    and -17 is 37.
24. In neganonary, 17 is 188
    and -17 is 21.
25. In negadecimal, 17 is 197
    and -17 is 23.
26. In negelevenary, 17 is 1X6
    and -17 is 25.
27. In negadozenal, 17 is 1E5
    and -17 is 27.
28. In negabaker's dozenal, 17 is 1Z4
    and -17 is 29.
29. In negabiseptimal, 17 is 1D3
    and -17 is 2B.
30. In negatriquinary, 17 is 1E2
    and -17 is 2D.
31. In negahex, 17 is 1F1
    and -17 is 2F.
32. In negasuboptimal, 17 is 1G0
    and -17 is 10.