6 HI-I + 2 KMnVIIO4 3 I20 + 2 MnIVO2 + 2 KOH + 2 H2O

This is an oxidation-reduction (redox) reaction:

2 MnVII + 6 e- 2 MnIV (reduction)

6 I-I - 6 e- 6 I0 (oxidation)

KMnO4 is an oxidizing agent, HI is a reducing agent.