Yes, and it does appear you have quite a bit battery left, 3.9V per cell is likely a little over 50% charged.

A typical resting voltage vs capacity table, based on discharging at 1C to 3V. Of course this will vary some by cell but most such tests/tables I have seen over the years are fairly close.

4.20v = 100%
4.03v = 76%
3.86v = 52%
3.83v = 42%
3.79v = 30%
3.70v = 11%
3.6?v = 0%

Most recommend limiting discharge to about 80% (20% left) for better lipo life.