In the process of converting a raster image, the number of colors in it decreased from 19683 to 27.

In the process of converting a raster image, the number of colors in it decreased from 19683 to 27. How many times has the information volume of this image decreased?

The information volume is calculated by the formula: I = N * i, where N is not important to us, and i is the power of the number 2, the result with which shows the number of colors.
i1 = 15 since 2 ^ 15 = 32768 and this is the closest number
i2 = 5 in the same way
15 more than 5 3 times
Answer: 3.