257928257 has 2 divisors, whose sum is σ = 257928258. Its totient is φ = 257928256.

The previous prime is 257928247. The next prime is 257928283. The reversal of 257928257 is 752829752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 250873921 + 7054336 = 15839^2 + 2656^2 .

It is a cyclic number.

It is not a de Polignac number, because 257928257 - 2⁴ = 257928241 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (257928247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128964128 + 128964129.

It is an arithmetic number, because the mean of its divisors is an integer number (128964129).

Almost surely, 2^257928257 is an apocalyptic number.

It is an amenable number.

257928257 is a deficient number, since it is larger than the sum of its proper divisors (1).

257928257 is an equidigital number, since it uses as much as digits as its factorization.

257928257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 705600, while the sum is 47.

The square root of 257928257 is about 16060.1449868922. The cubic root of 257928257 is about 636.5506624473.

The spelling of 257928257 in words is "two hundred fifty-seven million, nine hundred twenty-eight thousand, two hundred fifty-seven".