N,K,M = map(int,input().split())

def prime_factorize(n):
	prime = []
	f = 2
	while(f * f <= n):
		if(n % f == 0):
			n //= f
			cnt = 1
			while(n % f == 0):
				n //= f
				cnt += 1
			prime.append((f,cnt))
		f += 1
	if(n != 1):
		prime.append((n,1))
	return prime

def digit_sum(n, p):
	res = 0
	while(n):
		res += n % p
		n //= p
	return res

def kummer(N,K,p,q):
	R = N - K
	cnt = (digit_sum(R, p) - digit_sum(N, p) + digit_sum(K, p)) // (p - 1)
	return cnt // q

prime = prime_factorize(M)
ans = 10 ** 18
for p,c in prime:
	cnt = kummer(N,K,p,c)
	if(ans > cnt):
		ans = cnt

print(ans)