def v(p,n):
    cnt = 0
    k = 1
    while True:
        d = n//pow(p,k)
        if d==0:
            break
        cnt += d
        k += 1
    return cnt
P = list(range(10**6))
for i in range(2,10**6):
    if i*i>10**6:break
    for j in range(i*i,10**6,i):
        P[j] = P[i]
Q = []
for i in range(2,10**6):
    if P[i]==i:
        Q.append(i)
N,K,M = map(int,input().split())
C = {}
x = M
for p in Q:
    if x%p==0:
        cnt = 0
        while x%p==0:
            x //= p
            cnt += 1
        C[p] = cnt
if x>1:
    C[x] = 1
D = {p:0 for p in C}
for p in C:
    D[p] = v(p,N)-v(p,K)-v(p,N-K)
ans = 100
for p in C:
    ans = min(ans,D[p]//C[p])
print(ans)