891657113728 has 32 divisors (see below), whose sum is σ = 1776850711020. Its totient is φ = 445702425600.

The previous prime is 891657113717. The next prime is 891657113729. The reversal of 891657113728 is 827311756198.

891657113728 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 840830313024 + 50826800704 = 916968^2 + 225448^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is not an unprimeable number, because it can be changed into a prime (891657113729) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 530383 + ... + 1436878.

Almost surely, 2^891657113728 is an apocalyptic number.

It is an amenable number.

891657113728 is a deficient number, since it is larger than the sum of its proper divisors (885193597292).

891657113728 is a wasteful number, since it uses less digits than its factorization.

891657113728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1970816 (or 1970804 counting only the distinct ones).

The product of its digits is 5080320, while the sum is 58.

The spelling of 891657113728 in words is "eight hundred ninety-one billion, six hundred fifty-seven million, one hundred thirteen thousand, seven hundred twenty-eight".