115

Number
$115$ (one hundred and fifteen) is:


 * $5 \times 23$


 * The $25$th lucky number:
 * $1, 3, 7, 9, 13, 15, 21, 25, 31, 33, 37, 43, 49, 51, 63, 67, 73, 75, 79, 87, 93, 99, 105, 111, 115, \ldots$


 * The $8$th number after $1, 3, 22, 66, 70, 81, 94$ whose $\sigma$ value is square:

Also see