168

Number
$168$ (one hundred and sixty-eight) is:


 * $2^3 \times 3 \times 7$


 * The $25$th highly abundant number after $1$, $2$, $3$, $4$, $6$, $8$, $10$, $12$, $16$, $18$, $20$, $24$, $30$, $36$, $42$, $48$, $60$, $72$, $84$, $90$, $96$, $108$, $120$, $144$:
 * $\sigma \left({168}\right) = 480$


 * The smallest positive integer which can be expressed as the sum of $2$ odd primes in $13$ ways.


 * The $1$st element of the $1$st set of $3$ integers $T$ such that $m \tau \left({m}\right)$ is equal for each $m \in T$:
 * $168 \times \tau \left({168}\right) = 192 \times \tau \left({192}\right) = 224 \times \tau \left({224}\right) = 2688$


 * The number of primes with no more than $3$ digits:
 * $2, 3, 5, 7, 11, 13, 17, 19, 23, \ldots, 937, 941, 947, 953, 967, 971, 977, 983, 991, 997$


 * The $11$th integer $n$ after $1, 3, 15, 30, 35, 56, 70, 78, 105, 140$ with the property that $\tau \left({n}\right) \mathrel \backslash \phi \left({n}\right) \mathrel \backslash \sigma \left({n}\right)$:
 * $\tau \left({168}\right) = 16$, $\phi \left({168}\right) = 48$, $\sigma \left({168}\right) = 480$

Also see