From WO'N's site:
According to The Book of the Balance by Gâbir ibn Hayyân, an alchemist and a soufi, the shape (sura) of every thing in the world is 17; 17 is the very basis of the theory of the Balance and must be regarded as the canon of the equilibrium of every thing.
Well, now I know why, in my mind, I will always be 17.

Also from the same site:
From the ancient times, the Chi'ist mystics had venerated the number 17; this veneration has its origins in the ancient Pythagorean speculations lying on the letters in the Greek alphabet... 17 represented the number of those who would rise from the dead and each one of those people was to receive one of the 17 letters of the alphabet, making up the highest name of God, which is certainly related to the blade of the Star, arcanum 17 in the Tarot game whose symbolism evokes mutation, rebirth, and which Dr Allendy considers to be Karmic Liberation.

And lastly:
To the ancient Greeks, 17 represents the number of consonants in the alphabet, with 9 silent consonants and 8 semi-vowels or semi-consonants. These numbers were also tightly linked with musical theory and the harmony of the spheres.