At 170cm(5'5), you should weigh 114 - 144lb (51.7 - 65.3kg)
weighing in at the top end of the normal range at 64.7kg, you are fine.
That is just a guideline though, if you wanted to achieve a leaner physique, you could still lose weight if you wanted to, however that would be up to you for aesthetic purposes.
Just make sure if you go about losing weight you follow a proper diet/exercise regimen.
