To find the order of magnitude of a number $x\cdot 10^n$:

• If $x\le \sqrt{10}\approx 3.16$, the order of magnitude is $10^n$.
• If $x>\sqrt{10}\approx 3.16$, the order of magnitude is $10^{n+1}$. Here, $x=6.37$, which is greater than $3.16$. Therefore, the order of magnitude is $10^{6+1}=10^7\text{ m}$.