11968267721 has 4 divisors (see below), whose sum is σ = 12136834944. Its totient is φ = 11799700500.

The previous prime is 11968267697. The next prime is 11968267747. The reversal of 11968267721 is 12776286911.

It is a happy number.

11968267721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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: 12776286911 = 57077 ⋅223843.

It is a cyclic number.

It is not a de Polignac number, because 11968267721 - 2⁶ = 11968267657 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 11968267721.

It is not an unprimeable number, because it can be changed into a prime (11968267621) 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 in 3 ways as a sum of consecutive naturals, for example, 84283505 + ... + 84283646.

It is an arithmetic number, because the mean of its divisors is an integer number (3034208736).

Almost surely, 2^11968267721 is an apocalyptic number.

It is an amenable number.

11968267721 is a deficient number, since it is larger than the sum of its proper divisors (168567223).

11968267721 is an equidigital number, since it uses as much as digits as its factorization.

11968267721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168567222.

The product of its digits is 508032, while the sum is 50.

The spelling of 11968267721 in words is "eleven billion, nine hundred sixty-eight million, two hundred sixty-seven thousand, seven hundred twenty-one".