Answer
$162=2\times3^4$
Work Step by Step
$\ \ 162$
$\swarrow\searrow$
$2\ \ \ \ 81$
$\ \ \ \swarrow\searrow$
$\ \ \ \ 3\ \ \ \ \ \ 27$
$\ \ \ \ \ \ \ \ \ \swarrow\searrow$
$\ \ \ \ \ \ \ \ \ 3\ \ \ \ \ \ \ 9$
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ \swarrow\searrow$
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ 3\ \ \ \ \ \ \ 3$