42,209

Number
$42 \, 209$ (forty-two thousand, two hundred and nine) is:


 * The $4413$th prime number


 * The $19$th prime $p$ such that $p \# + 1$, where $p \#$ denotes primorial (product of all primes up to $p$) of $p$, is prime:
 * $2$, $3$, $5$, $7$, $11$, $31$, $379$, $1019$, $1021$, $2657$, $3229$, $4547$, $4787$, $11 \, 549$, $13 \, 649$, $18 \, 523$, $23 \, 801$, $24 \, 029$, $42 \, 209$