12311221213021 has 4 divisors (see below), whose sum is σ = 12318149307772. Its totient is φ = 12304293118272.

The previous prime is 12311221213019. The next prime is 12311221213073. The reversal of 12311221213021 is 12031212211321.

It is a happy number.

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 3438484119225 + 8872737093796 = 1854315^2 + 2978714^2 .

It is a cyclic number.

It is not a de Polignac number, because 12311221213021 - 2¹ = 12311221213019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12311221212983 and 12311221213001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12311221211021) 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, 3464044710 + ... + 3464048263.

It is an arithmetic number, because the mean of its divisors is an integer number (3079537326943).

Almost surely, 2^{12311221213021} is an apocalyptic number.

It is an amenable number.

12311221213021 is a deficient number, since it is larger than the sum of its proper divisors (6928094751).

12311221213021 is an equidigital number, since it uses as much as digits as its factorization.

12311221213021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6928094750.

The product of its (nonzero) digits is 288, while the sum is 22.

Adding to 12311221213021 its reverse (12031212211321), we get a palindrome (24342433424342).

The spelling of 12311221213021 in words is "twelve trillion, three hundred eleven billion, two hundred twenty-one million, two hundred thirteen thousand, twenty-one".