#![allow(unused_imports)]
use std::cmp::*;
use std::collections::*;
use std::io::Write;
use std::ops::Bound::*;

#[allow(unused_macros)]
macro_rules! debug {
    ($($e:expr),*) => {
        #[cfg(debug_assertions)]
        $({
            let (e, mut err) = (stringify!($e), std::io::stderr());
            writeln!(err, "{} = {:?}", e, $e).unwrap()
        })*
    };
}

fn main() {
    let v = read_vec::<i128>();
    let (n, k, m) = (v[0], v[1], v[2]);
    let mut sq = 1;
    for i in 1.. {
        if i * i > m {
            sq = i - 1;
            break;
        }
    }
    let primes = get_primes(sq + 1);

    let mut mm = m;
    let mut dividors = vec![];
    for p in primes {
        if mm % p == 0 {
            dividors.push(p);
            while mm % p == 0 {
                mm /= p;
            }
        }
    }
    if mm > 1 {
        dividors.push(mm);
    }
    debug!(dividors);
    let ans = dividors
        .iter()
        .map(|&x| count(x, n) - count(x, n - k) - count(x, k))
        .min()
        .unwrap();
    println!("{}", ans);
}

fn count(p: i128, n: i128) -> i128 {
    let mut cur = p;
    let mut ret = 0;
    while cur <= n {
        ret += n / cur;
        cur *= p;
    }
    ret
}

fn get_primes(n: i128) -> Vec<i128> {
    let mut is_prime = vec![true; n as usize + 1];
    let mut primes = Vec::new();
    is_prime[0] = false;
    is_prime[1] = false;

    for i in 2..n + 1 {
        if is_prime[i as usize] {
            primes.push(i);
            let mut j = 2 * i;
            while j <= n {
                is_prime[j as usize] = false;
                j += i;
            }
        }
    }
    primes
}

fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}