210

Number
$210$ (two hundred and ten) is:


 * $2 \times 3 \times 5 \times 7$


 * The $4$th primorial, after $1, 2, 6, 30$ (counting $1$ as the zeroth):
 * $210 = 7 \# = 2 \times 3 \times 5 \times 7$
 * Hence the smallest positive integer with $4$ distinct prime factors.


 * The $11$th number after $1, 3, 22, 66, 70, 81, 94, 115, 119, 170$ whose $\sigma$ value is square:

Also see