18045919081 has 2 divisors, whose sum is σ = 18045919082. Its totient is φ = 18045919080.

The previous prime is 18045919063. The next prime is 18045919097. The reversal of 18045919081 is 18091954081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12074493456 + 5971425625 = 109884^2 + 77275^2 .

It is a cyclic number.

It is not a de Polignac number, because 18045919081 - 2³¹ = 15898435433 is a prime.

It is a super-2 number, since 2×18045919081² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18045919061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9022959540 + 9022959541.

It is an arithmetic number, because the mean of its divisors is an integer number (9022959541).

Almost surely, 2^18045919081 is an apocalyptic number.

It is an amenable number.

18045919081 is a deficient number, since it is larger than the sum of its proper divisors (1).

18045919081 is an equidigital number, since it uses as much as digits as its factorization.

18045919081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 103680, while the sum is 46.

The spelling of 18045919081 in words is "eighteen billion, forty-five million, nine hundred nineteen thousand, eighty-one".