import math

A, B, K = map(int, input().split())

if A == B:
    print(A*K)
else:
    l = min(A, B)
    r = max(A, B) * K

    C = A * B / math.gcd(A, B)

    while l < r:
        m = (l+r) // 2
        a = m // A
        b = m // B
        c = m // C
        if a + b - c == K:
            m = max(a * A, b * B)
            break
        elif a + b - c < K:
            l = m
        else:
            r = m
            
    print(m)