# エラトステネスのふるい
def Eratosthenes(maxNum):
    sieve = list(range(2,maxNum+1))
    result = []
    while sieve:
        prime = sieve[0]
        sieve = [x for x in sieve if x % prime]
        result.append(prime)
    return result
 
N=int(input())
primes = Eratosthenes(N)
tree = [2]    # 探索する二分木．各素数を加算するorしない
s=2           # 加算する素数の合計値
result = -1
 
while tree:
    if len(tree) < len(primes) and s+primes[len(tree)] <= N:
        tree.append(primes[len(tree)])
    else:   # 加算中の最大の素数を外すところまで戻る
        while(tree):
            if tree[-1]:
                tree[-1] = 0
                break
            else:
                tree.pop()
    s = sum(tree)
    if s == N:
        treeElements = [x for x in tree if x]
        if len(treeElements) > result:
            result = len(treeElements)
print(result)