Let \( S \) denote the set of \( 4 \)-digit numbers \( abcd \) such that \( a>b>c>d \) and \( P \) denote the set of \( 5 \)-digit numbers having product of its digits equal to \( 20 \). Then \( n(S)+n(P) \) is equal to \( \_\_\_\_\_\_\_\_ \).
