1223

Number
$1223$ (one thousand, two hundred and twenty-three) is:


 * The $200$th prime number


 * The $43$rd Sophie Germain prime after $2$, $3$, $5$, $11$, $23$, $29$, $41$, $\ldots$, $761$, $809$, $911$, $953$, $1013$, $1019$, $1031$, $1049$, $1103$:
 * $2 \times 1223 + 1 = 2447$, which is prime.