To simplify the expression \( 2^2 / 2^{-4} \) using the properties of integer exponents, we can apply the following property:
\[ \frac{a^m}{a^n} = a^{m-n} \]
In this case, we have \( a = 2 \), \( m = 2 \), and \( n = -4 \). So, we can write:
\[ \frac{2^2}{2^{-4}} = 2^{2 - (-4)} = 2^{2 + 4} = 2^6 \]
Now, to find \( 2^6 \):
\[ 2^6 = 64 \]
Thus, the final answer is:
\[ \boxed{64} \]