To convert meters to kilometers, you can divide the number of meters by 1,000 (since 1 kilometer is equal to 1,000 meters).
Given:
\[ 3.875 \times 10^9 \text{ meters} \]
To convert to kilometers:
\[ \frac{3.875 \times 10^9 \text{ meters}}{1,000} = 3.875 \times 10^9 \div 10^3 = 3.875 \times 10^{9-3} = 3.875 \times 10^6 \text{ kilometers} \]
So, the exact conversion of \(3.875 \times 10^9\) meters to kilometers is:
\[ \boxed{3.875 \times 10^6} \text{ kilometers} \]