231433331 has 2 divisors, whose sum is σ = 231433332. Its totient is φ = 231433330.

The previous prime is 231433313. The next prime is 231433333. The reversal of 231433331 is 133334132.

Together with previous prime (231433313) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-231433331 is a prime.

It is a super-2 number, since 2×231433331² = 107122773395511122, which contains 22 as substring.

Together with 231433333, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 231433297 and 231433306.

It is not a weakly prime, because it can be changed into another prime (231433333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115716665 + 115716666.

It is an arithmetic number, because the mean of its divisors is an integer number (115716666).

Almost surely, 2^231433331 is an apocalyptic number.

231433331 is a deficient number, since it is larger than the sum of its proper divisors (1).

231433331 is an equidigital number, since it uses as much as digits as its factorization.

231433331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1944, while the sum is 23.

The square root of 231433331 is about 15212.9330176663. The cubic root of 231433331 is about 613.9626737275.

Adding to 231433331 its reverse (133334132), we get a palindrome (364767463).

The spelling of 231433331 in words is "two hundred thirty-one million, four hundred thirty-three thousand, three hundred thirty-one".