211

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Number

$211$ (two hundred and eleven) is:

The $47$th prime number


The $41$st lucky number:
$1$, $3$, $7$, $9$, $13$, $15$, $21$, $\ldots$, $163$, $169$, $171$, $189$, $193$, $195$, $201$, $205$, $211$, $\ldots$


The $5$th balanced prime after $5$, $53$, $157$, $173$:
$211 = \dfrac {199 + 223} 2$


The $11$th of $11$ primes of the form $2 x^2 + 11$:
$2 \times 10^2 + 11 = 211$ (Previous)


The $4$th Euclid number after $3$, $7$, $31$:
$211 = p_4\# + 1 = 2 \times 3 \times 5 \times 7 + 1$


The $5$th Euclid prime after $2$, $3$, $7$, $31$:
$211 = p_4\# + 1 = 2 \times 3 \times 5 \times 7 + 1$


Also see