* Atomic Number: The atomic number of an element is defined by the number of protons in its nucleus. This number is fundamental and determines the element's identity.

* Isotopes: Isotopes of an element have the same number of protons (same atomic number) but differ in the number of neutrons.

Since the question only provides the number of neutrons, it doesn't give us enough information to determine the atomic number.

To find the atomic number, we need to know the element in question. Here's why:

* Example: Let's say the element is Boron (B). Boron has an atomic number of 5. This means all Boron atoms have 5 protons. If an isotope of Boron has 6 neutrons, it would be Boron-11 (5 protons + 6 neutrons = 11 atomic mass units).

To answer your question fully, we need the element's identity.