257717969 has 2 divisors, whose sum is σ = 257717970. Its totient is φ = 257717968.

The previous prime is 257717939. The next prime is 257717981. The reversal of 257717969 is 969717752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 253223569 + 4494400 = 15913^2 + 2120^2 .

It is a cyclic number.

It is not a de Polignac number, because 257717969 - 2¹⁶ = 257652433 is a prime.

It is a super-2 number, since 2×257717969² = 132837103090969922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 257717969.

It is not a weakly prime, because it can be changed into another prime (257717939) 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 as a sum of consecutive naturals, namely, 128858984 + 128858985.

It is an arithmetic number, because the mean of its divisors is an integer number (128858985).

Almost surely, 2^257717969 is an apocalyptic number.

It is an amenable number.

257717969 is a deficient number, since it is larger than the sum of its proper divisors (1).

257717969 is an equidigital number, since it uses as much as digits as its factorization.

257717969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1666980, while the sum is 53.

The square root of 257717969 is about 16053.5967620966. The cubic root of 257717969 is about 636.3776229078.

The spelling of 257717969 in words is "two hundred fifty-seven million, seven hundred seventeen thousand, nine hundred sixty-nine".