231604257 has 4 divisors (see below), whose sum is σ = 308805680. Its totient is φ = 154402836.

The previous prime is 231604249. The next prime is 231604271. The reversal of 231604257 is 752406132.

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 not a de Polignac number, because 231604257 - 2³ = 231604249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (231604057) 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, 38600707 + ... + 38600712.

It is an arithmetic number, because the mean of its divisors is an integer number (77201420).

Almost surely, 2^231604257 is an apocalyptic number.

It is an amenable number.

231604257 is a deficient number, since it is larger than the sum of its proper divisors (77201423).

231604257 is an equidigital number, since it uses as much as digits as its factorization.

231604257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77201422.

The product of its (nonzero) digits is 10080, while the sum is 30.

The square root of 231604257 is about 15218.5497666499. The cubic root of 231604257 is about 614.1137847176.

The spelling of 231604257 in words is "two hundred thirty-one million, six hundred four thousand, two hundred fifty-seven".