11810535591 has 4 divisors (see below), whose sum is σ = 15747380792. Its totient is φ = 7873690392.

The previous prime is 11810535587. The next prime is 11810535601. The reversal of 11810535591 is 19553501811.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19553501811 = 3 ⋅6517833937.

It is not a de Polignac number, because 11810535591 - 2² = 11810535587 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 (11810635591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1968422596 + ... + 1968422601.

It is an arithmetic number, because the mean of its divisors is an integer number (3936845198).

Almost surely, 2^11810535591 is an apocalyptic number.

11810535591 is a deficient number, since it is larger than the sum of its proper divisors (3936845201).

11810535591 is an equidigital number, since it uses as much as digits as its factorization.

11810535591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3936845200.

The product of its (nonzero) digits is 27000, while the sum is 39.

The spelling of 11810535591 in words is "eleven billion, eight hundred ten million, five hundred thirty-five thousand, five hundred ninety-one".