27696 is a member of OEIS A100329: a(n) = -a(n-1) -a(n-2) -a(n-3) +a(n-4), a(0)=0, a(1)=1, a(2)=-1, a(3)=0. The sequence can be generated as follows (permalink):

INPUT

# a(n) = -a(n-1) -a(n-2) -a(n-3) +a(n-4), a(0)=0, a(1)=1, a(2)=-1, a(3)=0.

a,b,c,d=0,1,-1,0

L=[a,b,c,d]

for n in [1..45]:

  e=-d-c-b+a

  L.append(e)

  a,b,c,d=b,c,d,e

print(L)

OUTPUT

[0, 1, -1, 0, 0, 2, -3, 1, 0, 4, -8, 5, -1, 8, -20, 18, -7, 17, -48, 56, -32, 41, -113, 160, -120, 114, -267, 433, -400, 348, -648, 1133, -1233, 1096, -1644, 2914, -3599, 3425, -4384, 7472, -10112, 10449, -12193, 19328, -27696, 31010, -34835, 50849, -74720]

27696 is a Smith number since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

27696 is an untouchable number because it is not equal to the sum of proper divisors of any number.

27696 is an abundant, Zumkeller and pseudoperfect number.

27696 reaches a home prime after 25 steps.

27696 has an aliquot sequence that does NOT terminate after 121 steps.

27696 has a reverse and add sequence that does NOT terminate after 2000 cycles.

27696 can be rendered as a digit equation as follows:

2 + 7 = -6 + 9 + 6