import sys
input = sys.stdin.readline

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


x=M
# 素因数分解
import math 
L=int(math.sqrt(x))

FACT=dict()

for i in range(2,L+2):
    while x%i==0:
        FACT[i]=FACT.get(i,0)+1
        x=x//i

if x!=1:
    FACT[x]=FACT.get(x,0)+1

LANS=1<<65

for f in FACT:
    ANS=0

    for i in range(1,65):
        if pow(f,i)>10**18:
            break
        ANS+=N//pow(f,i)

        ANS-=K//pow(f,i)
        ANS-=(N-K)//pow(f,i)

    LANS=min(LANS,ANS//FACT[f])

print(LANS)