"27 letters (aabcdeeefghijlmnooprrstuuvy) and 12 numbers (011223456789) for a total of 39."

Gus Molina pointed out that the answer could also be 43, if case sensitive letters are counted separately:

"A,D,F,J,M,N,O,S,2a,b,c,3e,g,h,i,l,m,n,o,p,2r,s,t,2u,v,y => 31

Numbers: 0,2x1,2x2,3,4,5,6,7,8,9 => 12"

Technically 43 is probably the better answer, but since the problem did not specify capitalization, 39 is also accepted.

Winner: Kevin Lombardo

Contest Statistics: 19 answers submitted, 13 answers correct, 68.42% accuracy. Chance of a correct answer winning: 7.69%.