n, m, k = map(int, input().split())

def count(x):
    s = 0
    for i in range(1, n + 1):
        s += min(m, x // i)
    return s

l, r = 1, n * m
while l < r:
    mid = (l + r) // 2
    if count(mid) >= k:
        r = mid
    else:
        l = mid + 1

print(l)