18544038881 has 2 divisors, whose sum is σ = 18544038882. Its totient is φ = 18544038880.

The previous prime is 18544038847. The next prime is 18544038959. The reversal of 18544038881 is 18883044581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9748600225 + 8795438656 = 98735^2 + 93784^2 .

It is a cyclic number.

It is not a de Polignac number, because 18544038881 - 2¹⁰ = 18544037857 is a prime.

It is a super-3 number, since 3×18544038881³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (18544038841) 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, 9272019440 + 9272019441.

It is an arithmetic number, because the mean of its divisors is an integer number (9272019441).

Almost surely, 2^18544038881 is an apocalyptic number.

It is an amenable number.

18544038881 is a deficient number, since it is larger than the sum of its proper divisors (1).

18544038881 is an equidigital number, since it uses as much as digits as its factorization.

18544038881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 983040, while the sum is 50.

The spelling of 18544038881 in words is "eighteen billion, five hundred forty-four million, thirty-eight thousand, eight hundred eighty-one".