num=int(input())
a=1
while True:
if num%7==0:
d=num//7
print('7'*d)
break
else:
b=num-4*a
if b%7==0:
c=b//7
print('4'*a+'7'*c)
break
elif b==4:
print('4'*(a+1))
break
elif b<4:
print('-1')
break
else:
a+=1
49A - Sleuth | 1541A - Pretty Permutations |
1632C - Strange Test | 673A - Bear and Game |
276A - Lunch Rush | 1205A - Almost Equal |
1020B - Badge | 1353A - Most Unstable Array |
770A - New Password | 1646B - Quality vs Quantity |
80A - Panoramix's Prediction | 1354B - Ternary String |
122B - Lucky Substring | 266B - Queue at the School |
1490A - Dense Array | 1650B - DIV + MOD |
1549B - Gregor and the Pawn Game | 553A - Kyoya and Colored Balls |
1364A - XXXXX | 1499B - Binary Removals |
1569C - Jury Meeting | 108A - Palindromic Times |
46A - Ball Game | 114A - Cifera |
776A - A Serial Killer | 25B - Phone numbers |
1633C - Kill the Monster | 1611A - Make Even |
1030B - Vasya and Cornfield | 1631A - Min Max Swap |