12111111012 has 384 divisors, whose sum is σ = 40317419520. Its totient is φ = 2726760960.

The previous prime is 12111110933. The next prime is 12111111029. The reversal of 12111111012 is 21011111121.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 16299913 + ... + 16300655.

It is an arithmetic number, because the mean of its divisors is an integer number (104993280).

Almost surely, 2^12111111012 is an apocalyptic number.

12111111012 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 12111111012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20158709760).

12111111012 is an abundant number, since it is smaller than the sum of its proper divisors (28206308508).

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

12111111012 is a wasteful number, since it uses less digits than its factorization.

12111111012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 863 (or 861 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 12.

Adding to 12111111012 its reverse (21011111121), we get a palindrome (33122222133).

The spelling of 12111111012 in words is "twelve billion, one hundred eleven million, one hundred eleven thousand, twelve".