def factorization(n):
    arr = dict()
    temp = n
    for i in range(2, int(-(-n ** 0.5 // 1)) + 1):
        if temp % i == 0:
            cnt = 0
            while temp % i == 0:
                cnt += 1
                temp //= i
            arr[i] = cnt

    if temp != 1:
        arr[temp] = 1

    if not arr and n != 1:
        arr[n] = 1

    return arr


def f(n, m):
    """n! が m**x で割り切れる最大のx"""
    res = 0
    while n:
        n //= m
        res += n
    return res


N, K, M = map(int, input().split())
fac = factorization(M)
ans = float("inf")
for k, v in fac.items():
    ans = min(ans, (f(N, k) - f(K, k) - f(N - K, k)) // v)
print(ans)