Great demiprismated icosiheptaheptacontadipeton

The great demiprismated icosiheptaheptacontadipeton or ghopjak, also called the demiruncicantitruncated 221 polytope, is a convex uniform polypeton. It consists of 27 great prismated demipenteracts, 27 great rhombated demipenteracts, 72 great prismated hexatera, and 216 decachoric prisms. 2 great prismated demipenteracts, 1 great rhombated demipenteract, 2 great prismated hexatera, and 1 decachoric prism join at each vertex. As the name suggests, it is the demiruncicantitruncation of the icosiheptaheptacontadipeton.