12191961869 has 4 divisors (see below), whose sum is σ = 12192276096. Its totient is φ = 12191647644.

The previous prime is 12191961829. The next prime is 12191961889. The reversal of 12191961869 is 96816919121.

12191961869 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: 96816919121 = 13 ⋅7447455317.

It is a cyclic number.

It is not a de Polignac number, because 12191961869 - 2²⁴ = 12175184653 is a prime.

It is a super-2 number, since 2×12191961869² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12191961869.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12191961829) 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, 89099 + ... + 179784.

It is an arithmetic number, because the mean of its divisors is an integer number (3048069024).

Almost surely, 2^12191961869 is an apocalyptic number.

It is an amenable number.

12191961869 is a deficient number, since it is larger than the sum of its proper divisors (314227).

12191961869 is an equidigital number, since it uses as much as digits as its factorization.

12191961869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314226.

The product of its digits is 419904, while the sum is 53.

The spelling of 12191961869 in words is "twelve billion, one hundred ninety-one million, nine hundred sixty-one thousand, eight hundred sixty-nine".