1492 The kth Factor of n

You are given two positive integers n and k. A factor of an integer n is defined as an integer i where n % i == 0.

Consider a list of all factors of n sorted in ascending order, return the kth factor in this list or return -1 if n has less than k factors.

Example 1:

Input: n = 12, k = 3
Output: 3
Explanation: Factors list is [1, 2, 3, 4, 6, 12], the 3rd factor is 3.

Example 2:

Input: n = 7, k = 2
Output: 7
Explanation: Factors list is [1, 7], the 2nd factor is 7.

Example 3:

Input: n = 4, k = 4
Output: -1
Explanation: Factors list is [1, 2, 4], there is only 3 factors. We should return -1.

Constraints:

• 1 <= k <= n <= 1000

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class Solution:
    def kthFactor(self, n: int, k: int) -> int:
        divisors, sqrt_n = [], int(n**0.5)
        for x in range(1, sqrt_n+1):
            if n % x == 0:
                k -= 1
                if k == 0:
                    return x
                divisors.append(x)
        if sqrt_n * sqrt_n == n:
            k += 1
        if k <= len(divisors):
            return n // divisors[-k]
        else:
            return -1