11823564208681 has 9 divisors (see below), whose sum is σ = 11844883661221. Its totient is φ = 11802283078432.

The previous prime is 11823564208661. The next prime is 11823564208693. The reversal of 11823564208681 is 18680246532811.

The square root of 11823564208681 is 3438541.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 10198704118681 + 1624860090000 = 3193541^2 + 1274700^2 .

It is not a de Polignac number, because 11823564208681 - 2¹¹ = 11823564206633 is a prime.

It is a super-2 number, since 2×11823564208681² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11823564208661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2121577011 + ... + 2121582583.

Almost surely, 2^{11823564208681} is an apocalyptic number.

11823564208681 is the 3438541-st square number.

11823564208681 is the 1719271-st centered octagonal number.

It is an amenable number.

11823564208681 is a deficient number, since it is larger than the sum of its proper divisors (21319452540).

11823564208681 is an frugal number, since it uses more digits than its factorization.

11823564208681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12380 (or 6190 counting only the distinct ones).

The product of its (nonzero) digits is 4423680, while the sum is 55.

The spelling of 11823564208681 in words is "eleven trillion, eight hundred twenty-three billion, five hundred sixty-four million, two hundred eight thousand, six hundred eighty-one".