265

Number
$265$ (two hundred and sixty-five) is:


 * $5 \times 53$


 * The $6$th subfactorial after $0$, $1$, $2$, $9$, $44$:
 * $265 = \, !6 = 6! \left({1 - \dfrac 1 {1!} + \dfrac 1 {2!} - \dfrac 1 {3!} + \dfrac 1 {4!} - \dfrac 1 {5!} + \dfrac 1 {6!} }\right)$


 * The $14$th number after $1$, $3$, $22$, $66$, $70$, $81$, $94$, $115$, $119$, $170$, $210$, $214$, $217$ whose $\sigma$ value is square:


 * The $10$th Smith number after $4$, $22$, $27$, $58$, $85$, $94$, $121$, $166$, $202$:
 * $2 + 6 + 5 = 5 + 5 + 3 = 13$


 * The $14$th positive integer after $50$, $65$, $85$, $125$, $130$, $145$, $170$, $185$, $200$, $205$, $221$, $250$, $260$ which can be expressed as the sum of two square numbers in two or more different ways:
 * $265 = 16^2 + 3^2 = 12^2 + 11^2$


 * The $17$th positive integer $n$ after $0$, $1$, $5$, $25$, $29$, $41$, $49$, $61$, $65$, $85$, $89$, $101$, $125$, $145$, $149$, $245$ such that the Fibonacci number $F_n$ ends in $n$

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