First, we must know the following conversions:
1 pm = 10⁻¹² m
1 mm = 10⁻³ m
Therefore,
1 pm = 10⁻⁹ mm
The radius of the atom is 131 pm, which means that the span of one atom, the diameter, is 262 pm.
Number of atoms needed = distance to be covered / span of one atom
Number of atoms needed = 2.4 / 262 x 10⁻⁹
Number of atoms needed = 9.16 x 10⁷
9.16 x 10⁷ atoms of niobium will be needed
