If an object loses 21.7x10^19 electrons, what would be the electric charge of this object, measured in coulombs?

The charge of the electron is a fundamental magnitude. It is the elemental charge (nothing can hava a fraction of this charge):

Charge of one electron = - 1.6 * 10 ^ - 19 C

So, if the object losses 21.7 * 10 ^ 19 electrons it has lost

21.7 * 10^ 19 * * -1.6 * 10^ - 19 C = - 34.72 C

So, lossing this negative charge, leaves the object with a positive charge of 34.72C.

+ 34.72C