142
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Number
$142$ (one hundred and forty-two) is:
- $2 \times 71$
- The $5$th positive integer after $1$, $7$, $102$, $110$ the sum of whose divisors is a cube:
- $\map {\sigma_1} {142} = 216 = 6^3$
- The $18$th nontotient after $14$, $26$, $34$, $38$, $50$, $62$, $68$, $74$, $76$, $86$, $90$, $94$, $98$, $114$, $118$, $122$, $124$, $134$:
- $\nexists m \in \Z_{>0}: \map \phi m = 142$
- where $\map \phi m$ denotes the Euler $\phi$ function
- The $59$th positive integer after $2$, $3$, $4$, $7$, $8$, $\ldots$, $95$, $96$, $100$, $101$, $102$, $107$, $112$, $116$, $124$, $136$, $137$, $141$ which cannot be expressed as the sum of distinct pentagonal numbers.