231918317 has 4 divisors (see below), whose sum is σ = 231978240. Its totient is φ = 231858396.

The previous prime is 231918293. The next prime is 231918353. The reversal of 231918317 is 713819132.

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 a de Polignac number, because none of the positive numbers 2^k-231918317 is a prime.

It is a super-2 number, since 2×231918317² = 107572211520224978, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231948317) 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, 23723 + ... + 32040.

It is an arithmetic number, because the mean of its divisors is an integer number (57994560).

Almost surely, 2^231918317 is an apocalyptic number.

It is an amenable number.

231918317 is a deficient number, since it is larger than the sum of its proper divisors (59923).

231918317 is an equidigital number, since it uses as much as digits as its factorization.

231918317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59922.

The product of its digits is 9072, while the sum is 35.

The square root of 231918317 is about 15228.8645998315. The cubic root of 231918317 is about 614.3912428632.

The spelling of 231918317 in words is "two hundred thirty-one million, nine hundred eighteen thousand, three hundred seventeen".