Answer
$a^3b(4b-3)(16b^2+12b+9)$
Work Step by Step
Factoring the $GCF=a^3b$ results to $a^3b(64b^3-27)$. Using $a^3+b^3=(a+b)(a^2-ab+b^2)$ or the factoring of two cubes, then,
\begin{array}{l}
a^3b(64b^3-27)
\\=
a^3b[(4b)+(-3)][(4b)^2-(4b)(-3)+(-3)^2]
\\=
a^3b(4b-3)(16b^2+12b+9)
.\end{array}