12111000021 has 12 divisors (see below), whose sum is σ = 17570734272. Its totient is φ = 8038430376.

The previous prime is 12111000019. The next prime is 12111000043. The reversal of 12111000021 is 12000011121.

It is a happy number.

It is not a de Polignac number, because 12111000021 - 2¹ = 12111000019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 12110999967 and 12111000012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12111000001) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2961981 + ... + 2966066.

It is an arithmetic number, because the mean of its divisors is an integer number (1464227856).

Almost surely, 2^12111000021 is an apocalyptic number.

It is an amenable number.

12111000021 is a deficient number, since it is larger than the sum of its proper divisors (5459734251).

12111000021 is a wasteful number, since it uses less digits than its factorization.

12111000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5928280 (or 5928277 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 12111000021 its reverse (12000011121), we get a palindrome (24111011142).

The spelling of 12111000021 in words is "twelve billion, one hundred eleven million, twenty-one", and thus it is an aban number.