N,K=map(int, input().split())
A=list(map(int, input().split()))

def make_divisors(n):
    lower_divisors , upper_divisors = [], []
    i = 1
    while i*i <= n:
        if n % i == 0:
            lower_divisors.append(i)
            if i != n // i:
                upper_divisors.append(n//i)
        i += 1
    return lower_divisors + upper_divisors[::-1]

B=[]
for a in A:
  for b in make_divisors(a):
    B.append(b)

B=sorted(list(set(B)))
ans=1
for b in B:
  if b==1:
    continue 
  c=0
  for a in A:
    cc=a%b 
    c+=min(cc,b-cc)
  if c<=K:
    ans=b
print(ans)