2131121312321 has 4 divisors (see below), whose sum is σ = 2143882517952. Its totient is φ = 2118360106692.

The previous prime is 2131121312263. The next prime is 2131121312371. The reversal of 2131121312321 is 1232131211312.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2131121312321 - 2²⁶ = 2131054203457 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2131121312371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6380602565 + ... + 6380602898.

It is an arithmetic number, because the mean of its divisors is an integer number (535970629488).

Almost surely, 2^{2131121312321} is an apocalyptic number.

It is an amenable number.

2131121312321 is a deficient number, since it is larger than the sum of its proper divisors (12761205631).

2131121312321 is a wasteful number, since it uses less digits than its factorization.

2131121312321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12761205630.

The product of its digits is 432, while the sum is 23.

Adding to 2131121312321 its reverse (1232131211312), we get a palindrome (3363252523633).

It can be divided in two parts, 2131121 and 312321, that added together give a palindrome (2443442).

The spelling of 2131121312321 in words is "two trillion, one hundred thirty-one billion, one hundred twenty-one million, three hundred twelve thousand, three hundred twenty-one".