18012055681 has 9 divisors (see below), whose sum is σ = 18202597569. Its totient is φ = 17823492036.

The previous prime is 18012055657. The next prime is 18012055709. The reversal of 18012055681 is 18655021081.

The square root of 18012055681 is 134209.

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

It is not a de Polignac number, because 18012055681 - 2¹⁹ = 18011531393 is a prime.

It is a super-2 number, since 2×18012055681² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18012055681.

It is not an unprimeable number, because it can be changed into a prime (18012055631) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 13822876 + ... + 13824178.

It is an arithmetic number, because the mean of its divisors is an integer number (2022510841).

Almost surely, 2^18012055681 is an apocalyptic number.

18012055681 is the 134209-th square number.

18012055681 is the 67105-th centered octagonal number.

It is an amenable number.

18012055681 is a deficient number, since it is larger than the sum of its proper divisors (190541888).

18012055681 is an frugal number, since it uses more digits than its factorization.

18012055681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2812 (or 1406 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 37.

The spelling of 18012055681 in words is "eighteen billion, twelve million, fifty-five thousand, six hundred eighty-one".