how many positive dividers that aren't multiple of 2 are there in the number 52920? i need to know how many positive dividers that aren't multiple of 2 are there in the number 52920.
How do i eliminate multiples of 2?

Just keep dividing by $2$ until it is no longer even:
$52920=2 \cdot 26460$
$2646- = 2 \cdot 13230$
$13230 = 2 \cdot 6615$
OK, so find out the dividers of $6615$.
Now, since it ends in $5$ it's divisible by $5$, so divide by $5$:
$6615 = 5 \cdot 1323$
Also, any number is divisible by $3$ iff the sum of its digits is divisible by $3$, so this number is divisible by $3$ since $1+3+2+3=9$:
$1323 = 3 \cdot 441$
$4+4+1=9$, so still divisible by $3$:
$441=3 \cdot 147$
$1+4+7=12$ so still divisible by $3$:
$147=3 \cdot 49$
OK, and we know $49 = 7 \cdot 7$
OK, so we know $6615=3^3 \cdot 5 \cdot 7^2$
So, any positive divisor will be of the form $3^i \cdot 5^j \cdot 7^k$ with $0 \le i \le 3$, $0\le j \le 1$, and $0 \le k \le 2$
So, final question left for you: in how many ways can I pick $i,j,k$? 
