231618121 has 4 divisors (see below), whose sum is σ = 264706432. Its totient is φ = 198529812.

The previous prime is 231618103. The next prime is 231618131. The reversal of 231618121 is 121816132.

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 231618121 - 2⁵ = 231618089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (231618131) 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, 16544145 + ... + 16544158.

It is an arithmetic number, because the mean of its divisors is an integer number (66176608).

Almost surely, 2^231618121 is an apocalyptic number.

It is an amenable number.

231618121 is a deficient number, since it is larger than the sum of its proper divisors (33088311).

231618121 is an equidigital number, since it uses as much as digits as its factorization.

231618121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33088310.

The product of its digits is 576, while the sum is 25.

The square root of 231618121 is about 15219.0052565863. The cubic root of 231618121 is about 614.1260382397.

The spelling of 231618121 in words is "two hundred thirty-one million, six hundred eighteen thousand, one hundred twenty-one".