257017905 has 12 divisors (see below), whose sum is σ = 445497780. Its totient is φ = 137076192.

The previous prime is 257017903. The next prime is 257017913. The reversal of 257017905 is 509710752.

It can be written as a sum of positive squares in 2 ways, for example, as 60233121 + 196784784 = 7761^2 + 14028^2 .

It is not a de Polignac number, because 257017905 - 2¹ = 257017903 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 257017905.

It is not an unprimeable number, because it can be changed into a prime (257017903) 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 11 ways as a sum of consecutive naturals, for example, 2855710 + ... + 2855799.

It is an arithmetic number, because the mean of its divisors is an integer number (37124815).

Almost surely, 2^257017905 is an apocalyptic number.

It is an amenable number.

257017905 is a deficient number, since it is larger than the sum of its proper divisors (188479875).

257017905 is a wasteful number, since it uses less digits than its factorization.

257017905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5711520 (or 5711517 counting only the distinct ones).

The product of its (nonzero) digits is 22050, while the sum is 36.

The square root of 257017905 is about 16031.7779737620. Note that the first 3 decimals coincide. The cubic root of 257017905 is about 635.8008825468.

The spelling of 257017905 in words is "two hundred fifty-seven million, seventeen thousand, nine hundred five".