Living on pure glycogen?
You asked three questions here, so I'll answer them one by one.

Yes, you can survive with glycogen as the only source of carbohydrates, assuming that you also take other nutrients like proteins, fats, vitamins, etc. also because carbohydrates cannot supplement all of them. See this article:

There are three macronutrients: carbohydrates, protein and fats. Macronutrients are essential for proper body functioning, and the body requires large amounts of them. All macronutrients must be obtained through diet; the body cannot produce macronutrients on its own.


No, there's no way to calculate this. If we were talking about glucose, a definite range could be given. But since glycogen is a polymer with variable amount of glucose molecules linked together (at least I couldn't find an exact number),  its not possible to tell how many glycogen molecules are needed for the daily metabolism in the body.

Glycogen is an organic, non-polar polymer, insoluble in water just like starch. It does not have a specific taste, but once you eat it, an enzyme called salivary amylase will break it into glucose, maltose and limit dextrins, causing it to taste a bit sweet. See this article:

This enzyme acts on starch, glycogen and related polysaccharides and oligosaccharides producing beta-maltose by an inversion.




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