import math

# Function to calculate sum of divisors

def divisorsSum(n) :

sum = 0 # Initialize sum of prime factors

# Note that this loop runs till square

# root of n

i = 1

while i<= math.sqrt(n) :

if (n % i == 0) :

# If divisors are equal, take only one

# of them

if (n / i == i) :

sum = sum + i

else : # Otherwise take both

sum = sum + i;

sum = sum + (n / i)

i = i + 1

return sum

# Function to check Deficient Number

def isDeficient(n) :

# Check if sum(n) < 2 * n

return (divisorsSum(n) < (2 * n))

# Driver program to test above function

if ( isDeficient(12) ):

print "YES"

else :

print "NO"

if ( isDeficient(15) ) :

print "YES"

else :

print "NO"

# This Code is contributed by Nikita Tiwari