None. cubic inches are a measure of volume, inches are a measure of length.
There are no cubic inches in an inch. Cubic inches are units of volume and inches are units of length.
To have cubic inches you need a length, width, and height in inches.
27 liters means it has a capacity of about 1,647.6 cubic inches.
1,728 cubic inches.
There are 1,728 cubic inches to the cubic foot
There are 1,728 cubic inches in a cubic foot.
1728 cubic inches = 28316.8 cubic centimeters
I'm not sure your question is going to get the answer your looking for but here is how it works. cubic feet is width in feet times height in feet times depth in feet (w*h*d=v or volume). 1 cubic foot equals 1728 cubic inches. If the 26 for depth and width is measured in inches then your "oven" height is 1728 divided by 26 then divided by 26 again (h=v/w/d). That would make your oven height 2.56 inches. That just doesn't seem to be reasonable for an oven so you may want to edit your question.
2.81 cubic inches.
111.92 cubic inches.
That is 79.33 cubic inches.
About 0.061 cubic inches per cubic centimeter.
1 cubic foot = 1,728 cubic inches.
About 0.061 cubic inches per cubic centimeter.