11581506720 has 432 divisors, whose sum is σ = 46321486848. Its totient is φ = 2627251200.

The previous prime is 11581506707. The next prime is 11581506737. The reversal of 11581506720 is 2760518511.

11581506720 is a `hidden beast` number, since 1 + 1 + 5 + 81 + 506 + 72 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 10654017 + ... + 10655103.

It is an arithmetic number, because the mean of its divisors is an integer number (107225664).

Almost surely, 2^11581506720 is an apocalyptic number.

11581506720 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 11581506720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23160743424).

11581506720 is an abundant number, since it is smaller than the sum of its proper divisors (34739980128).

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

11581506720 is a wasteful number, since it uses less digits than its factorization.

11581506720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1273 (or 1255 counting only the distinct ones).

The product of its (nonzero) digits is 16800, while the sum is 36.

The spelling of 11581506720 in words is "eleven billion, five hundred eighty-one million, five hundred six thousand, seven hundred twenty".