from collections import Counter
from functools import reduce

def find_prime_factors(n):
    factors = []

    i = 2

    while i <= n / i:
        if n % i == 0:
            factors.append(i)
            n = int(n / i)
        else:
            i += 1

    factors.append(n)

    return factors

def divisible(rng):
    factors = None

    for num in rng:
        nums = find_prime_factors(num)
        count = Counter(nums)

        if (factors == None):
            factors = count
        else:
            for key, value in count.items():
                if (not factors[key] or value > factors[key]):
                    factors[key] = value

    return factors
    # max_num = max(rng)


factors = divisible(range(1, 21))

# print(factors)

# reduce(def fnc(value, key): print(value), factors.items())

result = 1
for key, value in factors.items():
    result *= key ** value

print(result)