Factor x3y6 + 27z42.

(xy3 + 3z39)(x2y9 – 3xy3z39 + 9z1,521)

(xy3 + 3z39)(x2y6 – 3xy3z39 + 9z78)

(x3y6 + 27z42)(x6y12 – 27x3y6z42 + 729z84)

(xy2 + 3z14)(x2y4 – 3xy2z14 + 9z28)