This is very much inspired by this question.
Take the first 26 primes and relate each one to a letter of the alphabet.
On this occasion, you may choose how each number is mapped to each letter (so, for example we may have A=67, B=31, etc) but each letter must be mapped to a distinct prime.
The score of a word is the product of the primes corresponding to the letters (so if we mapped A=31, L=3 then the score of ALL is 31x3x3 = 279)
What is the longest word which scores at most 1,000,000 for some mapping?