180. Find $N=p q$, if $\varphi(N)=120$, and the numbers $p$ and $q$ are twin prime numbers, i.e., $p-q=2$.
180. From the system of equations $\left\{\begin{array}{l}p q\left(1-\frac{1}{p}\right)\left(1-\frac{1}{q}\right)=120 \\ p-q=2\end{array}\right.$ we find $p=13, q=11$.

Answer. 143.