The soul may not be destroyed. The soul goes on forever. Like the number pi, it is without cessation or conclusion. Like pi it is a constant. Pi is an irrational number, incapable of being made into a fraction, impossible to divide from itself. So, too, the soul is an irrational, indivisible equation that perfectly expresses one thing: you.
The number Pi does not go on forever. It sits at a particular spot on the number scale, just a little past 3. Every number is constant. The number 2 is always the number 2. No number is ever "made into" a fraction. It can only be expressed as a fraction. The fact that irrational numbers cannot be so expressed, does not make them any less rational in the cognitive sense. As for divisibility, all irrational numbers may be divided, including Pi.
None of which has any bearing or parallel with the soul.