Let \( A = \{1, 2, 3, 5, 8, 9\} \). Then the number of possible functions \( f : A \to A \) such that \( f(m \cdot n) = f(m) \cdot f(n) \) for every \( m, n \in A \) with \( m \cdot n \in A \) is equal to _________.