11685959521 has 4 divisors (see below), whose sum is σ = 11686176432. Its totient is φ = 11685742612.

The previous prime is 11685959497. The next prime is 11685959561. The reversal of 11685959521 is 12595958611.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12595958611 = 761 ⋅16551851.

It is a cyclic number.

It is not a de Polignac number, because 11685959521 - 2⁹ = 11685959009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11685959561) 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, 41106 + ... + 158308.

It is an arithmetic number, because the mean of its divisors is an integer number (2921544108).

Almost surely, 2^11685959521 is an apocalyptic number.

It is an amenable number.

11685959521 is a deficient number, since it is larger than the sum of its proper divisors (216911).

11685959521 is an equidigital number, since it uses as much as digits as its factorization.

11685959521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216910.

The product of its digits is 972000, while the sum is 52.

The spelling of 11685959521 in words is "eleven billion, six hundred eighty-five million, nine hundred fifty-nine thousand, five hundred twenty-one".