Professor's Cube the Eastsheen 5×5×5 and the V-Cube 5 are designed with different mechanisms in an attempt to remedy the fragility of the original design. There are 98 pieces on the exterior of the cube: 8 corners, 36 edges, and 54 centers (48 movable, 6 fixed). Any permutation of the corners is possible, including odd permutations, giving 8! possible arrangements. Seven of the corners can be independently rotated, and the orientation of the eighth depends on the other seven, giving 3 (or 2,187) combinations. There are 54 centers. Six of these (the center square of each face) are fixed in position. The
Helicopter Cube number of permutations is reduced to 24!/(4!) arrangements. The reducing factor comes about because there are 24 (4!) ways to arrange the four pieces of a given colour. This is raised to the sixth power because there are six colours. This gives a total number of permutations of The expanded number is (approximately trillion or 12 trilliard on the long scale or 12 sextillion on the short scale) To count non-cube positions, we need to count all the possible shapes (ignoring the colours). Counting those shapes is tricky, since sometimes moves are blocked purely due to the shape of the