18609092581 has 2 divisors, whose sum is σ = 18609092582. Its totient is φ = 18609092580.

The previous prime is 18609092549. The next prime is 18609092599. The reversal of 18609092581 is 18529090681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10471428900 + 8137663681 = 102330^2 + 90209^2 .

It is a cyclic number.

It is not a de Polignac number, because 18609092581 - 2⁵ = 18609092549 is a prime.

It is a super-2 number, since 2×18609092581² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18609092521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9304546290 + 9304546291.

It is an arithmetic number, because the mean of its divisors is an integer number (9304546291).

Almost surely, 2^18609092581 is an apocalyptic number.

It is an amenable number.

18609092581 is a deficient number, since it is larger than the sum of its proper divisors (1).

18609092581 is an equidigital number, since it uses as much as digits as its factorization.

18609092581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 311040, while the sum is 49.

The spelling of 18609092581 in words is "eighteen billion, six hundred nine million, ninety-two thousand, five hundred eighty-one".