n, k, m = map(int, input().split())

Prime = []
f = 2
while f * f <= m:
    if m % f == 0:
        cnt = 1
        m //= f
        while m % f == 0:
            m //= f
            cnt += 1
        Prime.append((f, cnt))
    f += 1
if m != 1:
    Prime.append((m, 1))

def legendre(n, k, p, cnt):
    r = n - k
    ans = 0
    while n:
        n //= p
        ans += n
    while k:
        k //= p
        ans -= k
    while r:
        r //= p
        ans -= r
    return ans // cnt

ans = 10**18
for prime, cnt in Prime:
    cnt = legendre(n, k, prime, cnt)
    ans = min(ans, cnt)
print(ans)