def trial_division(n) :
    a = []
    while (n % 2 == 0) :
        a.append(2)
        a //= 2
    f = 3
    while (f ** 2 <= n) :
        if n % f == 0 :
            a.append(f)
            n //= f
        else :
            f += 2
    if n != 1 : a.append(n)
    return a

a = sorted(a)
for i in a :
    if i > 2 :
        print(i)
        break