241

Number
$241$ (two hundred and forty-one) is:


 * The $53$rd prime number.


 * The smaller of the $3$rd pair of primes whose prime gap is $10$:
 * $251 - 241 = 10$


 * The $9$th Proth prime after $3$, $5$, $13$, $17$, $41$, $97$, $113$, $193$:
 * $241 = 15 \times 2^4 + 1$


 * The $2$nd of the $17$th pair of twin primes, with $241$


 * The $47$th lucky number:
 * $1$, $3$, $7$, $9$, $13$, $15$, $21$, $\ldots$, $193$, $195$, $201$, $205$, $211$, $219$, $223$, $231$, $235$, $237$, $241$, $\ldots$


 * The $47$th positive integer $n$ such that no factorial of an integer can end with $n$ zeroes.