target=10000
d=[0]*target
n=2
while n < target:
    for i in range(n+n,target,n):
        d[i]=d[i]+1
    n=n+1
    while n < target and d[n]>0:
        n=n+1

primeList=[k for k in range(2,target) if d[k]==0]

squareList=[2*i*i for i in range(1,100)]

n=33
notFound=True

while notFound:
    n+=2
    while n in primeList:
        n+=2
    i=0
    while squareList[i] < n and n-squareList[i] not in primeList:
        i+=1
    notFound=squareList[i] < n

print n