If $n=2^3 \cdot 3^2 \cdot 5$, how many even positive factors does $n$ have?
n = 2^3×3^2×5 = 360
360 =1, 2 | 3 | 4 | 5 | 6 | 8 | 9 | 10 | 12 | 15 | 18 | 20 | 24 | 30 | 36 | 40 | 45 | 60 | 72 | 90 | 120 | 180 | 360 (24 divisors)
Even divisors: 2, 4, 6, 8, 10, 12, 18, 20, 24, 30, 36, 40, 60, 72, 90, 120, 180, 360 =18
+142 
