231311210320121 has 4 divisors (see below), whose sum is σ = 231328098061812. Its totient is φ = 231294322578432.

The previous prime is 231311210320117. The next prime is 231311210320133. The reversal of 231311210320121 is 121023012113132.

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 1427998710121 + 229883211610000 = 1194989^2 + 15161900^2 .

It is a cyclic number.

It is not a de Polignac number, because 231311210320121 - 2² = 231311210320117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (231311210520121) 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, 8443850300 + ... + 8443877693.

It is an arithmetic number, because the mean of its divisors is an integer number (57832024515453).

Almost surely, 2^{231311210320121} is an apocalyptic number.

It is an amenable number.

231311210320121 is a deficient number, since it is larger than the sum of its proper divisors (16887741691).

231311210320121 is a wasteful number, since it uses less digits than its factorization.

231311210320121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16887741690.

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

Adding to 231311210320121 its reverse (121023012113132), we get a palindrome (352334222433253).

The spelling of 231311210320121 in words is "two hundred thirty-one trillion, three hundred eleven billion, two hundred ten million, three hundred twenty thousand, one hundred twenty-one".