18748399081 has 4 divisors (see below), whose sum is σ = 18923617872. Its totient is φ = 18573180292.

The previous prime is 18748399063. The next prime is 18748399097. The reversal of 18748399081 is 18099384781.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18748399081 - 2²³ = 18740010473 is a prime.

It is a super-2 number, since 2×18748399081² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18748399031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87609235 + ... + 87609448.

It is an arithmetic number, because the mean of its divisors is an integer number (4730904468).

Almost surely, 2^18748399081 is an apocalyptic number.

It is an amenable number.

18748399081 is a deficient number, since it is larger than the sum of its proper divisors (175218791).

18748399081 is a wasteful number, since it uses less digits than its factorization.

18748399081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175218790.

The product of its (nonzero) digits is 3483648, while the sum is 58.

The spelling of 18748399081 in words is "eighteen billion, seven hundred forty-eight million, three hundred ninety-nine thousand, eighty-one".