Determine the value of $123456123456 \div 10000001$.
Of course, with such large numbers, the purpose of the question is not to perform the division. Instead, we decompose the number into convenient parts.

$$
\begin{aligned}
123456123456 & =123456000000+123456=123456 \times 1000000+123456 \\
& =123456 \times(1000000+1)=123456 \times 1000001
\end{aligned}
$$

Therefore, $123456123456 \div 1000001=123456$.