257863609 has 2 divisors, whose sum is σ = 257863610. Its totient is φ = 257863608.

The previous prime is 257863607. The next prime is 257863631. The reversal of 257863609 is 906368752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 196084009 + 61779600 = 14003^2 + 7860^2 .

It is a cyclic number.

It is not a de Polignac number, because 257863609 - 2¹ = 257863607 is a prime.

Together with 257863607, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (257863607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128931804 + 128931805.

It is an arithmetic number, because the mean of its divisors is an integer number (128931805).

Almost surely, 2^257863609 is an apocalyptic number.

It is an amenable number.

257863609 is a deficient number, since it is larger than the sum of its proper divisors (1).

257863609 is an equidigital number, since it uses as much as digits as its factorization.

257863609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 544320, while the sum is 46.

The square root of 257863609 is about 16058.1321765640. The cubic root of 257863609 is about 636.4974756085.

The spelling of 257863609 in words is "two hundred fifty-seven million, eight hundred sixty-three thousand, six hundred nine".