18881084861 has 2 divisors, whose sum is σ = 18881084862. Its totient is φ = 18881084860.

The previous prime is 18881084851. The next prime is 18881084863. The reversal of 18881084861 is 16848018881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11282475961 + 7598608900 = 106219^2 + 87170^2 .

It is a cyclic number.

It is not a de Polignac number, because 18881084861 - 2¹⁸ = 18880822717 is a prime.

Together with 18881084863, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18881084863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9440542430 + 9440542431.

It is an arithmetic number, because the mean of its divisors is an integer number (9440542431).

Almost surely, 2^18881084861 is an apocalyptic number.

It is an amenable number.

18881084861 is a deficient number, since it is larger than the sum of its proper divisors (1).

18881084861 is an equidigital number, since it uses as much as digits as its factorization.

18881084861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 786432, while the sum is 53.

The spelling of 18881084861 in words is "eighteen billion, eight hundred eighty-one million, eighty-four thousand, eight hundred sixty-one".