11565520591 has 2 divisors, whose sum is σ = 11565520592. Its totient is φ = 11565520590.

The previous prime is 11565520567. The next prime is 11565520649. The reversal of 11565520591 is 19502556511.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11565520591 - 2²⁹ = 11028649679 is a prime.

It is a super-2 number, since 2×11565520591² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11565520511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5782760295 + 5782760296.

It is an arithmetic number, because the mean of its divisors is an integer number (5782760296).

Almost surely, 2^11565520591 is an apocalyptic number.

11565520591 is a deficient number, since it is larger than the sum of its proper divisors (1).

11565520591 is an equidigital number, since it uses as much as digits as its factorization.

11565520591 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 67500, while the sum is 40.

The spelling of 11565520591 in words is "eleven billion, five hundred sixty-five million, five hundred twenty thousand, five hundred ninety-one".