12111121121021 has 16 divisors (see below), whose sum is σ = 13111404716928. Its totient is φ = 11120799009600.

The previous prime is 12111121120957. The next prime is 12111121121023. The reversal of 12111121121021 is 12012112111121.

It is a cyclic number.

It is not a de Polignac number, because 12111121121021 - 2⁶ = 12111121120957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12111121121023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1289465 + ... + 5087726.

It is an arithmetic number, because the mean of its divisors is an integer number (819462794808).

Almost surely, 2^{12111121121021} is an apocalyptic number.

It is an amenable number.

12111121121021 is a deficient number, since it is larger than the sum of its proper divisors (1000283595907).

12111121121021 is a wasteful number, since it uses less digits than its factorization.

12111121121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6377972.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 12111121121021 its reverse (12012112111121), we get a palindrome (24123233232142).

The spelling of 12111121121021 in words is "twelve trillion, one hundred eleven billion, one hundred twenty-one million, one hundred twenty-one thousand, twenty-one".