come si fa 406 x 66703 ?

6 0 4 3 0 7 6 6 x = 8 1 1 2 1 0 0 0 2 4 4 8 2 6 3 3 4 2 6 3 3 4 2 1 1 8 1 4 1 8 0 7 2
x