#!/usr/bin/env python3

def nofdivs(n):
    sieve = [1] * n
    for p in range(2, n):
        if sieve[p] > 1:
            continue
        pw = 1
        while p**pw < n:
            for i in range(p**pw, n, p**pw):
                sieve[i] += sieve[i] // pw
            pw += 1
    return sieve


bound = 10**5

sieve = nofdivs(bound)

target = 500

for n in range(1, bound-1):
    if n % 2:
        a, b = (n + 1)//2, n
    else:
        a, b = n//2, n+1
    if sieve[a] * sieve[b] > target:
        print(a * b)
        break