257965397 has 2 divisors, whose sum is σ = 257965398. Its totient is φ = 257965396.

The previous prime is 257965387. The next prime is 257965403. The reversal of 257965397 is 793569752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 240064036 + 17901361 = 15494^2 + 4231^2 .

It is a cyclic number.

It is not a de Polignac number, because 257965397 - 2⁴ = 257965381 is a prime.

It is a super-3 number, since 3×257965397³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257965387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128982698 + 128982699.

It is an arithmetic number, because the mean of its divisors is an integer number (128982699).

Almost surely, 2^257965397 is an apocalyptic number.

It is an amenable number.

257965397 is a deficient number, since it is larger than the sum of its proper divisors (1).

257965397 is an equidigital number, since it uses as much as digits as its factorization.

257965397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3572100, while the sum is 53.

The square root of 257965397 is about 16061.3012237490. The cubic root of 257965397 is about 636.5812140397.

It can be divided in two parts, 2579 and 65397, that added together give a palindrome (67976).

The spelling of 257965397 in words is "two hundred fifty-seven million, nine hundred sixty-five thousand, three hundred ninety-seven".