94

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Number

$94$ (ninety-four) is:

$2 \times 47$


The $3$rd even integer after $2$, $4$ that cannot be expressed as the sum of $2$ prime numbers which are each one of a pair of twin primes


The $6$th Smith number after $4$, $22$, $27$, $58$, $85$:
$9 + 4 = 2 + 4 + 7 = 13$


The $7$th number after $1$, $3$, $22$, $66$, $70$, $81$ whose divisor sum is square:
$\map {\sigma_1} {94} = 144 = 12^2$


The $11$th integer $m$ such that $m! - 1$ (its factorial minus $1$) is prime:
$3$, $4$, $6$, $7$, $12$, $14$, $30$, $32$, $33$, $38$, $94$


The $12$th nontotient after $14$, $26$, $34$, $38$, $50$, $62$, $68$, $74$, $76$, $86$, $90$:
$\nexists m \in \Z_{>0}: \map \phi m = 94$
where $\map \phi m$ denotes the Euler $\phi$ function


The $18$th happy number after $1$, $7$, $10$, $13$, $19$, $23$, $28$, $31$, $32$, $44$, $49$, $68$, $70$, $79$, $82$, $86$, $91$:
$94 \to 9^2 + 4^2 = 81 + 16 = 97 \to 9^2 + 7^2 = 81 + 49 = 130 \to 1^2 + 3^2 + 0^2 = 1 + 9 + 0 = 10 \to 1^2 + 0^2 = 1$


The $32$nd semiprime:
$94 = 2 \times 47$


The $46$th positive integer after $2$, $3$, $4$, $7$, $8$, $\ldots$, $61$, $65$, $66$, $67$, $72$, $77$, $80$, $81$, $84$, $89$ which cannot be expressed as the sum of distinct pentagonal numbers


Also see


Sources