257811157 has 4 divisors (see below), whose sum is σ = 264099276. Its totient is φ = 251523040.

The previous prime is 257811149. The next prime is 257811161. The reversal of 257811157 is 751118752.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 43744996 + 214066161 = 6614^2 + 14631^2 .

It is a cyclic number.

It is not a de Polignac number, because 257811157 - 2³ = 257811149 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 (257811457) 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, 3143998 + ... + 3144079.

It is an arithmetic number, because the mean of its divisors is an integer number (66024819).

Almost surely, 2^257811157 is an apocalyptic number.

It is an amenable number.

257811157 is a deficient number, since it is larger than the sum of its proper divisors (6288119).

257811157 is an equidigital number, since it uses as much as digits as its factorization.

257811157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6288118.

The product of its digits is 19600, while the sum is 37.

The square root of 257811157 is about 16056.4989023137. The cubic root of 257811157 is about 636.4543160618.

The spelling of 257811157 in words is "two hundred fifty-seven million, eight hundred eleven thousand, one hundred fifty-seven".