Irreducibility of $x_1^2+x_2^2+...+x_n^2$ in $\mathbb{C}[x_1,...,x_n]$

Question

I wanted to know whether the polynomial function $x_1^2+...+x_n^2 \in \mathbb{C}[x_1,...,x_n]$ is irreducible in $\mathbb{C}[x_1,...,x_n]$ for $3 \leq n$ ?