5 characters.
77+68+77+65+0 = 287 = 7*41. 7 and 41 are the 4th and 13th primes. 13-4 = 9. The 9th prime? 23.
5 characters.
77+68+77+65+0 = 287 = 7*41. 7 and 41 are the 4th and 13th primes. 13-4 = 9. The 9th prime? 23.