In the sum of infinity, I am a single surd

In the sum of infinity, I am a single surd.
I'm a divisor from that great dividend.
I am a number pronounced by the primal Word
which continues counting itself without end.
In the sum of infinity, I am a single surd

Yet in that set of all that's possible
I have my special place.  For the string
cannot skip me.  I'm irreducible.
Together we form a perfect reckoning.
In the sum of infinity, I am a single surd.