If all LEDs are in series, you can do that. However most likely it's not worth it, if LEDs started to fail, other LEDs usually will fail soon too. Most likely these LEDs were overdriven by too high current. Also worth to mention that you should care about lumens, not Watts. A lot of Watts on cheap LED bulb often means it consumes a lot of power while emitting too little light for the power consumed, and is overdriving LEDs, thus severely reducing their lifespan.