27647 is a member of OEIS A272285: primes of the form 43*n^2 - 537*n + 2971 in order of increasing nonnegative values of n, here n=31. The sequence up to n=50 can be generated as follows:

INPUT

L=[]

for n in [0..50]:

  number = 43*n^2 - 537*n + 2971

  print(n,number,is_prime(number))

  if is_prime(number):

    L.append(number)

print()

print(L)

OUTPUT

0 2971 True

1 2477 True

2 2069 True

3 1747 True

4 1511 True

5 1361 True

6 1297 True

7 1319 True

8 1427 True

9 1621 True

10 1901 True

11 2267 True

12 2719 True

13 3257 True

14 3881 True

15 4591 True

16 5387 True

17 6269 True

18 7237 True

19 8291 True

20 9431 True

21 10657 True

22 11969 True

23 13367 True

24 14851 True

25 16421 True

26 18077 True

27 19819 True

28 21647 True

29 23561 True

30 25561 True

31 27647 True

32 29819 True

33 32077 True

34 34421 True

35 36851 False

36 39367 True

37 41969 True

38 44657 True

39 47431 True

40 50291 True

41 53237 False

42 56269 True

43 59387 True

44 62591 True

45 65881 True

46 69257 True

47 72719 True

48 76267 False

49 79901 True

50 83621 True

[2971, 2477, 2069, 1747, 1511, 1361, 1297, 1319, 1427, 1621, 1901, 2267, 2719, 3257, 3881, 4591, 5387, 6269, 7237, 8291, 9431, 10657, 11969, 13367, 14851, 16421, 18077, 19819, 21647, 23561, 25561, 27647, 29819, 32077, 34421, 39367, 41969, 44657, 47431, 50291, 56269, 59387, 62591, 65881, 69257, 72719, 79901, 83621]

27647 + SOD(26) = 27673 is also prime.

27647 can be rendered as a digit equation as follows:

2 + 7 - 6 = -4 + 7