231321131 has 4 divisors (see below), whose sum is σ = 232794672. Its totient is φ = 229847592.

The previous prime is 231321127. The next prime is 231321137. The reversal of 231321131 is 131123132.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 231321131 - 2² = 231321127 is a prime.

It is a super-2 number, since 2×231321131² = 107018931294238322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (231321137) 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, 736535 + ... + 736848.

It is an arithmetic number, because the mean of its divisors is an integer number (58198668).

Almost surely, 2^231321131 is an apocalyptic number.

231321131 is a deficient number, since it is larger than the sum of its proper divisors (1473541).

231321131 is a wasteful number, since it uses less digits than its factorization.

231321131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1473540.

The product of its digits is 108, while the sum is 17.

The square root of 231321131 is about 15209.2449187986. The cubic root of 231321131 is about 613.8634403300.

Adding to 231321131 its reverse (131123132), we get a palindrome (362444263).

The spelling of 231321131 in words is "two hundred thirty-one million, three hundred twenty-one thousand, one hundred thirty-one".