1575

Number
$1575$ (one thousand five hundred and seventy-five) is:


 * $3^2 \times 5^2 \times 7$


 * The $2$nd odd abundant number after $945$:
 * $\map {\sigma_1} {1575} - 1575 = 1649 > 1575$


 * With $1648$, an element of the $4$th quasiamicable pair:
 * $\map {\sigma_1} {1575} = \map {\sigma_1} {1648} = 3224 = 1575 + 1648 + 1$


 * The $50$th Zuckerman number after $1$, $2$, $3$, $4$, $5$, $6$, $7$, $8$, $9$, $11$, $12$, $\ldots$, $1176$, $1184$, $1197$, $1212$, $1296$, $1311$, $1332$, $1344$, $1416$:
 * $1575 = 9 \times 175 = 59 \times \paren {1 \times 5 \times 7 \times 5}$