how many protons neutrons and electrons does the human body have?
The result is that about 45% of the mass of the human body is due to neutrons, 55% is protons (0.027% is electrons). An average human weights around 80 kg, so there are 36 kg of neutrons. Each neutron weighs 1.675 E-27 kg. So there are 36/1.675 E-27 = 2.15 E28 neutrons in a human body.