ANSWER. The sum must be multiple of 12. Proof Let n be the "central" number in the sequence of 6 consecutive odd numbers (n-5), (n-3), (n-1), (n+1), (n+3), (n+5). Then the sum is 6n, and since n is an even number n = 2m, 6n = 12m is a multiple of 12. Since m can be any prime number, it shows that there is no other common divisor of the sums of this kind.