11581263391 has 4 divisors (see below), whose sum is σ = 11629720800. Its totient is φ = 11532805984.

The previous prime is 11581263367. The next prime is 11581263427. The reversal of 11581263391 is 19336218511.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 11581263391 - 2²³ = 11572874783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11581263191) 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, 24228346 + ... + 24228823.

It is an arithmetic number, because the mean of its divisors is an integer number (2907430200).

Almost surely, 2^11581263391 is an apocalyptic number.

11581263391 is a deficient number, since it is larger than the sum of its proper divisors (48457409).

11581263391 is an equidigital number, since it uses as much as digits as its factorization.

11581263391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48457408.

The product of its digits is 38880, while the sum is 40.

The spelling of 11581263391 in words is "eleven billion, five hundred eighty-one million, two hundred sixty-three thousand, three hundred ninety-one".