Let N be the number of ways to place the integers 1 through 12 in the 12 cells of a 2 \times 6 grid so that for any two cells sharing a side, the difference between the numbers in those cells is not divisible by 3 . One way to do this is shown below. Find the number of positive integer divisors of N.

\begin{tabular}{|c|c|c|c|c|c|} \hline 1 & 3 & 5 & 7 & 9 & 11 \\ \hline 2 & 4 & 6 & 8 & 10 & 12 \\ \hline \end{tabular}