11855881728 has 120 divisors (see below), whose sum is σ = 34296950688. Its totient is φ = 3942715392.

The previous prime is 11855881699. The next prime is 11855881733. The reversal of 11855881728 is 82718855811.

It is a happy number.

11855881728 is a `hidden beast` number, since 1 + 1 + 8 + 558 + 81 + 7 + 2 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2130726 + ... + 2136282.

Almost surely, 2^11855881728 is an apocalyptic number.

11855881728 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11855881728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17148475344).

11855881728 is an abundant number, since it is smaller than the sum of its proper divisors (22441068960).

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

11855881728 is an equidigital number, since it uses as much as digits as its factorization.

11855881728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6044 (or 6025 counting only the distinct ones).

The product of its digits is 1433600, while the sum is 54.

The spelling of 11855881728 in words is "eleven billion, eight hundred fifty-five million, eight hundred eighty-one thousand, seven hundred twenty-eight".