111

Number
$111$ (one hundred and eleven) is:


 * $3 \times 37$


 * The $35$th semiprime:
 * $111 = 3 \times 37$


 * The $3$rd repuint after $1, 11$


 * The $24$th lucky number:
 * $1, 3, 7, 9, 13, 15, 21, 25, 31, 33, 37, 43, 49, 51, 63, 67, 73, 75, 79, 87, 93, 99, 105, 111, \ldots$


 * The $7$th palindromic lucky number:
 * $1, 3, 7, 9, 33, 99, 111, \ldots$


 * The $4$th of the $17$ positive integers for which the value of the Euler $\phi$ function is $72$:
 * $73, 91, 95, 111, 117, 135, 146, 148, 152, 182, 190, 216, 222, 228, 234, 252, 270$


 * The magic constant of the smallest prime magic square.


 * A palindromic number whose square is also palindromic:

Also see

 * Square of Small-Digit Palindromic Number is Palindromic
 * Magic Constant of Smallest Prime Magic Square