n,k,m = map(int,input().split())
def prime_factorization(w,d):
    cnt = 2
    while w > 1:
        if cnt > int(w ** (1/2)):
            d[w] += 1
            break
        while w % cnt == 0:
            d[cnt] += 1
            w //= cnt
        cnt += 1
from collections import defaultdict
m_d = defaultdict(int)
prime_factorization(m,m_d)
def f_prime(N,K):
    d = defaultdict(int)
    def cul(nn,pm):
        for key in m_d.keys():
            cnt = 1
            while key ** cnt <= nn:
                if pm :
                    d[key] += nn // (key ** cnt)
                else:
                    d[key] -= nn // (key ** cnt)
                cnt += 1
    cul(N,True)
    cul(N-K,False)
    cul(K,False)
    return d
n_d = f_prime(n,k)
ans = 10000
for key in m_d.keys():
    ans = min(ans,n_d[key]//m_d[key])
print(ans)