256170257 has 8 divisors (see below), whose sum is σ = 298995456. Its totient is φ = 214902432.

The previous prime is 256170223. The next prime is 256170259. The reversal of 256170257 is 752071652.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256170257 - 2¹⁰ = 256169233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256170259) 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 in 7 ways as a sum of consecutive naturals, for example, 388988 + ... + 389645.

It is an arithmetic number, because the mean of its divisors is an integer number (37374432).

Almost surely, 2^256170257 is an apocalyptic number.

It is an amenable number.

256170257 is a deficient number, since it is larger than the sum of its proper divisors (42825199).

256170257 is an equidigital number, since it uses as much as digits as its factorization.

256170257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778687.

The product of its (nonzero) digits is 29400, while the sum is 35.

The square root of 256170257 is about 16005.3196469174. The cubic root of 256170257 is about 635.1011532081.

The spelling of 256170257 in words is "two hundred fifty-six million, one hundred seventy thousand, two hundred fifty-seven".