257989 has 2 divisors, whose sum is σ = 257990. Its totient is φ = 257988.

The previous prime is 257987. The next prime is 257993. The reversal of 257989 is 989752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 173889 + 84100 = 417^2 + 290^2 .

It is a cyclic number.

It is not a de Polignac number, because 257989 - 2¹ = 257987 is a prime.

Together with 257987, it forms a pair of twin primes.

It is a zygodrome in base 3.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128994 + 128995.

It is an arithmetic number, because the mean of its divisors is an integer number (128995).

2²⁵⁷⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

257989 is a deficient number, since it is larger than the sum of its proper divisors (1).

257989 is an equidigital number, since it uses as much as digits as its factorization.

257989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 40.

The square root of 257989 is about 507.9261757382. The cubic root of 257989 is about 63.6600628489.

The spelling of 257989 in words is "two hundred fifty-seven thousand, nine hundred eighty-nine".