1. If vectors $\boldsymbol{a}, \boldsymbol{b}, \boldsymbol{c}$ satisfy $\boldsymbol{a}+2 \boldsymbol{b}+3 \boldsymbol{c}=\mathbf{0}$, and $|\boldsymbol{a}|=6,|\boldsymbol{b}|=5,|\boldsymbol{c}|=2$, then $2 \boldsymbol{a} \cdot \boldsymbol{b}+6 \boldsymbol{b} \cdot \boldsymbol{c}+$ $3 \boldsymbol{c} \cdot \boldsymbol{a}=$ $\qquad$ .