Question

How to find out the number of factors ?

Answer 1

$8820=2\times 4410=2\times 2\times 2205=2\times 2\times 5\times 441=2\times 2\times 3\times 3\times 7\times 7\times 5=2^2\times 3^2\times 7^2\times 5$

Number of factors $=(p+1)(q+1)(r+1)(s+1)$ ; where p,q,r,s are the exponents of the prime factors of the number.
$=(2+1)(2+1)(2+1)(1+1)=3\times 3\times 3\times 2=54$.