Example:
15 Pm/L = 5.678118e+16 meter per US gallon
1 Pm/L = 3.785412e+15 meter per US gallon | 1 meter per US gallon = 2.641721e-16 Pm/L
Conversion Steps:
15 × (1e+15 / 0.264172052) = 5.678118e+16