12161111172 has 192 divisors, whose sum is σ = 34578862080. Its totient is φ = 3257895168.

The previous prime is 12161111167. The next prime is 12161111201. The reversal of 12161111172 is 27111116121.

It is a happy number.

12161111172 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 74607963 + ... + 74608125.

It is an arithmetic number, because the mean of its divisors is an integer number (180098240).

Almost surely, 2^12161111172 is an apocalyptic number.

12161111172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12161111172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17289431040).

12161111172 is an abundant number, since it is smaller than the sum of its proper divisors (22417750908).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12161111172 is a wasteful number, since it uses less digits than its factorization.

12161111172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319 (or 271 counting only the distinct ones).

The product of its digits is 168, while the sum is 24.

Adding to 12161111172 its reverse (27111116121), we get a palindrome (39272227293).

The spelling of 12161111172 in words is "twelve billion, one hundred sixty-one million, one hundred eleven thousand, one hundred seventy-two".