257831157 has 4 divisors (see below), whose sum is σ = 343774880. Its totient is φ = 171887436.

The previous prime is 257831153. The next prime is 257831183. The reversal of 257831157 is 751138752.

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 257831157 - 2² = 257831153 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257831153) 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, 42971857 + ... + 42971862.

It is an arithmetic number, because the mean of its divisors is an integer number (85943720).

Almost surely, 2^257831157 is an apocalyptic number.

It is an amenable number.

257831157 is a deficient number, since it is larger than the sum of its proper divisors (85943723).

257831157 is an equidigital number, since it uses as much as digits as its factorization.

257831157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85943722.

The product of its digits is 58800, while the sum is 39.

The square root of 257831157 is about 16057.1216910130. The cubic root of 257831157 is about 636.4707735305.

The spelling of 257831157 in words is "two hundred fifty-seven million, eight hundred thirty-one thousand, one hundred fifty-seven".