Multiplication is the most powerful operator

Logic Level 2

$\large 1 \; \square \; 2 \; \square \; 3 \; \square \; 4 \; \square \; 5 \; \square \; 6$

Fill in the boxes above with any of the four mathematical operators ( $+, -, \times , \div$ ). What is the maximum possible resultant number?