257863 has 2 divisors, whose sum is σ = 257864. Its totient is φ = 257862.

The previous prime is 257861. The next prime is 257867. The reversal of 257863 is 368752.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 257863 - 2¹ = 257861 is a prime.

Together with 257861, it forms a pair of twin primes.

It is a d-powerful number, because it can be written as 2¹⁷ + 5³ + 8³ + 7⁶ + 6⁵ + 3⁶ .

257863 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257861) 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, 128931 + 128932.

It is an arithmetic number, because the mean of its divisors is an integer number (128932).

2²⁵⁷⁸⁶³ is an apocalyptic number.

257863 is a deficient number, since it is larger than the sum of its proper divisors (1).

257863 is an equidigital number, since it uses as much as digits as its factorization.

257863 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10080, while the sum is 31.

The square root of 257863 is about 507.8021268171. The cubic root of 257863 is about 63.6496974533.

Subtracting 257863 from its reverse (368752), we obtain a square (110889 = 333²).

The spelling of 257863 in words is "two hundred fifty-seven thousand, eight hundred sixty-three".