12111110021 has 4 divisors (see below), whose sum is σ = 12114358092. Its totient is φ = 12107861952.

The previous prime is 12111109897. The next prime is 12111110027. The reversal of 12111110021 is 12001111121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8330212900 + 3780897121 = 91270^2 + 61489^2 .

It is a cyclic number.

It is not a de Polignac number, because 12111110021 - 2¹⁸ = 12110847877 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12111109984 and 12111110011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12111110027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1618436 + ... + 1625901.

It is an arithmetic number, because the mean of its divisors is an integer number (3028589523).

Almost surely, 2^12111110021 is an apocalyptic number.

It is an amenable number.

12111110021 is a deficient number, since it is larger than the sum of its proper divisors (3248071).

12111110021 is an equidigital number, since it uses as much as digits as its factorization.

12111110021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3248070.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 12111110021 its reverse (12001111121), we get a palindrome (24112221142).

It can be divided in two parts, 121111100 and 21, that added together give a palindrome (121111121).

The spelling of 12111110021 in words is "twelve billion, one hundred eleven million, one hundred ten thousand, twenty-one".