257630917 has 2 divisors, whose sum is σ = 257630918. Its totient is φ = 257630916.

The previous prime is 257630911. The next prime is 257630927. The reversal of 257630917 is 719036752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 257570401 + 60516 = 16049^2 + 246^2 .

It is a cyclic number.

It is not a de Polignac number, because 257630917 - 2³ = 257630909 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 257630917.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257630911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128815458 + 128815459.

It is an arithmetic number, because the mean of its divisors is an integer number (128815459).

Almost surely, 2^257630917 is an apocalyptic number.

It is an amenable number.

257630917 is a deficient number, since it is larger than the sum of its proper divisors (1).

257630917 is an equidigital number, since it uses as much as digits as its factorization.

257630917 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 79380, while the sum is 40.

The square root of 257630917 is about 16050.8852403847. The cubic root of 257630917 is about 636.3059629408.

The spelling of 257630917 in words is "two hundred fifty-seven million, six hundred thirty thousand, nine hundred seventeen".