local mce, mfl, msq, mmi, mma, mab = math.ceil, math.floor, math.sqrt, math.min, math.max, math.abs

local ffi = require("ffi")
local C = ffi.C
ffi.cdef[[
long long atoll(const char*);
]]

local function lltonumber(str)
  return C.atoll(str)
end


local function getprimes(x)
  local primes = {}
  local allnums = {}
  for i = 1, x do allnums[i] = true end
  for i = 2, x do
    if allnums[i] then
      table.insert(primes, i)
      local lim = mfl(x / i)
      for j = 2, lim do
        allnums[j * i] = false
      end
    end
  end
  return primes
end

local function getdivisorparts(x, primes)
  local prime_num = #primes
  local tmp = {}
  local lim = mce(msq(x))
  local primepos = 1
  local dv = primes[primepos]
  while primepos <= prime_num and dv <= lim do
    if x % dv == 0 then
      local cnt = 1
      x = mfl(x / dv)
      while x % dv == 0 do
        x = mfl(x / dv)
        cnt = cnt + 1
      end
      tmp[dv] = cnt
      lim = mce(msq(x))
    end
    if primepos == prime_num then break end
    primepos = primepos + 1
    dv = primes[primepos]
  end
  if x ~= 1 then
    tmp[x] = 1
  end
  return tmp
end

local n, k, m = io.read():match("(%d+) (%d+) (%d+)")
n = lltonumber(n)
k = lltonumber(k)
m = tonumber(m)
local primes = getprimes(1000 * 1000)
local dvp = getdivisorparts(m, primes)
local ret = false
for p, cnt in pairs(dvp) do
  local tmp = n
  local pl = 1LL * p
  local z = 0LL
  while 0LL < tmp do
    z = z + tmp / pl
    tmp = tmp / pl
  end
  tmp = k
  while 0LL < tmp do
    z = z - tmp / pl
    tmp = tmp / pl
  end
  if k < n then
    tmp = n - k
    while 0LL < tmp do
      z = z - tmp / pl
      tmp = tmp / pl
    end
  end
  if not ret then
    ret = z
  elseif z < ret then
    ret = z
  end
end
ret = tostring(ret):gsub("LL", "")
print(ret)