11505505591 has 2 divisors, whose sum is σ = 11505505592. Its totient is φ = 11505505590.

The previous prime is 11505505553. The next prime is 11505505603. The reversal of 11505505591 is 19550550511.

11505505591 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11505505591 - 2⁹ = 11505505079 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11505505591.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11515505591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5752752795 + 5752752796.

It is an arithmetic number, because the mean of its divisors is an integer number (5752752796).

Almost surely, 2^11505505591 is an apocalyptic number.

11505505591 is a deficient number, since it is larger than the sum of its proper divisors (1).

11505505591 is an equidigital number, since it uses as much as digits as its factorization.

11505505591 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28125, while the sum is 37.

The spelling of 11505505591 in words is "eleven billion, five hundred five million, five hundred five thousand, five hundred ninety-one".