18731649561504 has 96 divisors (see below), whose sum is σ = 56795964232896. Its totient is φ = 5342359941120.

The previous prime is 18731649561437. The next prime is 18731649561511. The reversal of 18731649561504 is 40516594613781.

It is a tau number, because it is divible by the number of its divisors (96).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 521696887 + ... + 521732790.

It is an arithmetic number, because the mean of its divisors is an integer number (591624627426).

Almost surely, 2^{18731649561504} is an apocalyptic number.

It is an amenable number.

18731649561504 is an abundant number, since it is smaller than the sum of its proper divisors (38064314671392).

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

18731649561504 is a wasteful number, since it uses less digits than its factorization.

18731649561504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1043429718 (or 1043429710 counting only the distinct ones).

The product of its (nonzero) digits is 21772800, while the sum is 60.

The spelling of 18731649561504 in words is "eighteen trillion, seven hundred thirty-one billion, six hundred forty-nine million, five hundred sixty-one thousand, five hundred four".