def fact(n):
  #fact(18)=[[2, 1],[3, 2]] (18 = 2**1 * 3**2)
  arr = []
  temp = n
  for i in range(2, int(-(-n**0.5//1))+1):
    if temp%i==0:
      cnt=0
      while temp%i==0:
        cnt+=1
        temp //= i
      arr.append([i, cnt])
  if temp!=1:
    arr.append([temp, 1])
  if arr==[]:
    arr.append([n, 1])
  return arr

n,k,m=map(int,input().split())
f=fact(m)
ans=10**18
for p,a in f:
  cnt=0
  tmp=p
  while tmp<1<<63:
    cnt+=n//tmp-(n-k)//tmp
    cnt-=k//tmp
    tmp*=p
  ans=min(ans,cnt//a)
print(ans)