To convert cubic meters to liters, you can use the conversion factor that 1 cubic meter (m³) is equal to 1,000 liters.
Given the volume of the Vehicle Assembly Building is 3,666,500 m³:
\[ 3,666,500 , \text{m}^3 \times 1,000 , \frac{\text{liters}}{\text{m}^3} = 3,666,500,000 , \text{liters} \]
Now, expressing this number in standard exponential notation, we have:
\[ 3,666,500,000 = 3.6665 \times 10^{9} , \text{liters} \]
Thus, the volume in liters, expressed in standard exponential notation with five significant digits, is:
\[ \boxed{3.6665 \times 10^{9}} , \text{liters} \]