11565081920 has 112 divisors (see below), whose sum is σ = 32116166400. Its totient is φ = 3965133312.

The previous prime is 11565081919. The next prime is 11565081923. The reversal of 11565081920 is 2918056511.

It is a tau number, because it is divible by the number of its divisors (112).

It is a super-2 number, since 2×11565081920² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11565081923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57077 + ... + 162443.

Almost surely, 2^11565081920 is an apocalyptic number.

11565081920 is a gapful number since it is divisible by the number (10) 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 11565081920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16058083200).

11565081920 is an abundant number, since it is smaller than the sum of its proper divisors (20551084480).

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

11565081920 is an equidigital number, since it uses as much as digits as its factorization.

11565081920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105405 (or 105381 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 38.

The spelling of 11565081920 in words is "eleven billion, five hundred sixty-five million, eighty-one thousand, nine hundred twenty".