18877089728 has 56 divisors (see below), whose sum is σ = 43326417792. Its totient is φ = 7992693504.

The previous prime is 18877089701. The next prime is 18877089733. The reversal of 18877089728 is 82798077881.

It is a tau number, because it is divible by the number of its divisors (56).

It is a super-2 number, since 2×18877089728² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 216650 + ... + 291017.

It is an arithmetic number, because the mean of its divisors is an integer number (773686032).

Almost surely, 2^18877089728 is an apocalyptic number.

It is an amenable number.

18877089728 is an abundant number, since it is smaller than the sum of its proper divisors (24449328064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18877089728 is an equidigital number, since it uses as much as digits as its factorization.

18877089728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 507769 (or 507759 counting only the distinct ones).

The product of its (nonzero) digits is 25288704, while the sum is 65.

The spelling of 18877089728 in words is "eighteen billion, eight hundred seventy-seven million, eighty-nine thousand, seven hundred twenty-eight".