The number, N, of neutrons in an atomic nucleus.

the number of neutrons in a nucleus, e.g., 56Fe contains 30 neutrons in its nucleus and 57Fe contains 31 neutrons in its nucleus

The number of neutrons in a nucleus. It is equivalent to the number of nucleons minus the atomic number or N = (A-Z). Symbol: . Related to atomic number. Related to mass number.

Neutron number () is a characteristic property of a specific isotope of an element, equal to the number of neutrons in the nucleus.

The total number of neutrons in the nucleus, N.