def isPrime(n):
    if n <= 1:
        return False
    else:
        i = 2
        while i**2 <= n:
            if n%i == 0:
                return False
            i += 1
        return True

M, D = input().split()

if len(D) == 1:
    D = "0"+D

print("Yes" if isPrime(int(M+D)) else "No")