To factor $ x^{3}+x^{2}+16x+16 $ we can use factoring by grouping:
Group $ \color{blue}{ x^{3} }$ with $ \color{blue}{ x^{2} }$ and $ \color{red}{ 16x }$ with $ \color{red}{ 16 }$ then factor each group.
$$ \begin{aligned} x^{3}+x^{2}+16x+16 = ( \color{blue}{ x^{3}+x^{2} } ) + ( \color{red}{ 16x+16 }) &= \\ &= \color{blue}{ x^{2}( x+1 )} + \color{red}{ 16( x+1 ) } = \\ &= (x^{2}+16)(x+1) \end{aligned} $$