ESP8266 ADC REFERENCE VOLTAGE
NodeMCU Amica R2 ADC aRef appears to be 3406, which is about 1064 mV when you account for the 220k/100k voltage divider before the ADC pin (ratio of .3125).
vOUT = vIN * (R2 / R1 + R2)
vOUT = 3406 * (100 / 220 + 100)
vOUT = 3406 * 0.3125
vOUT = 1064