from itertools import count


def calc_positive_divisors(num: int) -> dict[int, int]:
    if num < 2:
        raise ValueError

    divisors = {}
    for divisor in count(2):
        if divisor ** 2 > num:
            if num != 1:
                divisors[num] = 1
            break
        while num % divisor == 0 and num != 1:
            try:
                divisors[divisor] += 1
            except KeyError:
                divisors[divisor] = 1
            num //= divisor

    return divisors


def main():
    N = int(input())
    divisors = calc_positive_divisors(N)
    try:
        divisor_2 = divisors.pop(2)
        if divisor_2 >= 2:
            divisors[4] = 1
    except KeyError:
        pass

    print(min(divisors))


if __name__ == "__main__":
    main()