NaOH is a strong base(alkali). It dissociate completely to Na+ ion and OH- ion in the water.
NaOH(aq) → Na+(aq) + OH-(aq)
Usually pH values of NaOH solutions are high.
pH values of different concentration(moldm-3) NaOH solutions are shown below at 250C.
We can see, pH value is well above the 7. Therefore we can understand NaOH is a strong base.(alkali)
Na+ ion and OH- ions are stable in the water. Therefore Na+ and OH- ions do not hydrolysis.