18768855181 has 2 divisors, whose sum is σ = 18768855182. Its totient is φ = 18768855180.

The previous prime is 18768855173. The next prime is 18768855197. The reversal of 18768855181 is 18155886781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13112311081 + 5656544100 = 114509^2 + 75210^2 .

It is an emirp because it is prime and its reverse (18155886781) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18768855181 - 2³ = 18768855173 is a prime.

It is a super-2 number, since 2×18768855181² (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 (18768859181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9384427590 + 9384427591.

It is an arithmetic number, because the mean of its divisors is an integer number (9384427591).

Almost surely, 2^18768855181 is an apocalyptic number.

It is an amenable number.

18768855181 is a deficient number, since it is larger than the sum of its proper divisors (1).

18768855181 is an equidigital number, since it uses as much as digits as its factorization.

18768855181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4300800, while the sum is 58.

The spelling of 18768855181 in words is "eighteen billion, seven hundred sixty-eight million, eight hundred fifty-five thousand, one hundred eighty-one".