Factors of Sums of Powers of 100,000

Theorem
All integers $n$ of the form:
 * $n = \displaystyle \sum_{k \mathop = 0}^m 10^{5 k}$ for $m \in \Z_{> 0}$

are composite.

Proof
For even $m$, it can be seen by Divisibility by 11 that $11 \mathrel \backslash n$.