18401121808 has 10 divisors (see below), whose sum is σ = 35652173534. Its totient is φ = 9200560896.

The previous prime is 18401121799. The next prime is 18401121859. The reversal of 18401121808 is 80812110481.

It can be written as a sum of positive squares in only one way, i.e., 14503866624 + 3897255184 = 120432^2 + 62428^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 575035041 + ... + 575035072.

Almost surely, 2^18401121808 is an apocalyptic number.

It is an amenable number.

18401121808 is a deficient number, since it is larger than the sum of its proper divisors (17251051726).

18401121808 is a wasteful number, since it uses less digits than its factorization.

18401121808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1150070121 (or 1150070115 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 34.

The spelling of 18401121808 in words is "eighteen billion, four hundred one million, one hundred twenty-one thousand, eight hundred eight".