108

Number
$108$ (one hundred and eight) is:


 * $2^2 \times 3^3$


 * The number of distinct free heptominoes


 * The $15$th powerful number after $1$, $4$, $8$, $9$, $16$, $25$, $27$, $32$, $36$, $49$, $64$, $72$, $81$, $100$


 * The $22$nd highly abundant number after $1$, $2$, $3$, $4$, $6$, $8$, $10$, $12$, $16$, $18$, $20$, $24$, $30$, $36$, $42$, $48$, $60$, $72$, $84$, $90$, $96$:
 * $\map {\sigma_1} {108} = 280$


 * The $29$th positive integer which is not the sum of $1$ or more distinct squares:
 * $2$, $3$, $6$, $7$, $8$, $11$, $12$, $15$, $18$, $19$, $22$, $23$, $24$, $27$, $28$, $31$, $32$, $33$, $43$, $44$, $47$, $48$, $60$, $67$, $72$, $76$, $92$, $96$, $108$, $\ldots$


 * The $53$rd (strictly) positive integer after $1$, $2$, $3$, $\ldots$, $77$, $78$, $79$, $84$, $90$, $91$, $95$, $96$, $102$ which cannot be expressed as the sum of distinct primes of the form $6 n - 1$

Also see

 * Number of Heptominoes