Prime factorising, 53240=5×23×113.
We know, a perfect cube has multiples of 3 as powers of prime factors.
The prime factor 5 does not appear in triplet form.
Therefore, 53240 is not a perfect cube.
Since in the factorization, 5 appears only one time, we must divide the number 53240 by 5, then the quotient is a perfect cube.
∴53240÷5=10648
=22×22×22=223, which is a perfect cube.
∴ The smallest number by which 53240 should be divided to make it a perfect cube is 5.