#!/usr/bin/python
 
# Project Euler - Problem 12
 
# Find the first triangle number to have over 500 divisors
import math
 
i = 1
tri = 0
cnt = 2
last = 0
while True:
 
    tri += i
    i += 1
    cnt = 0
    for z in range(1,int(math.sqrt(tri))):
        if tri % z == 0:
            cnt += 2
    if cnt > 499:
        break
 
print tri