The strain energy in bending is given by the formula:
\[
U = \frac{P^2 L^2}{2EI}
\]
where:
- \( P = 1000 \, \text{N} \),
- \( L = R = 2 \, \text{m} \),
- \( E = 208 \times 10^9 \, \text{Pa} \),
- \( I = 26.7 \, \text{cm}^4 = 26.7 \times 10^{-8} \, \text{m}^4 \).
Substituting these values into the equation:
\[
U = \frac{1000^2 \times 2^2}{2 \times 208 \times 10^9 \times 26.7 \times 10^{-8}} \approx 56.58 \, \text{Nm}.
\]
Thus, the bending strain energy is \( \boxed{56.58} \, \text{Nm}. \)