Let $$\overrightarrow a = 2\widehat i + \widehat j -2 \widehat k$$ and $\overrightarrow b = \widehat i + \widehat j$. Let $\overrightarrow c$ be a vector such that $$\left| {\overrightarrow c - \overrightarrow a } \right| = 3$$, $$\left| {\left( {\overrightarrow a \times \overrightarrow b } \right) \times \overrightarrow c } \right| = 3$$ and the angle between $\overrightarrow c$ and $\overrightarrow a \times \overrightarrow b$ is $30^\circ$. Then $\overrightarrow a .\overrightarrow c$ is equal to :