257078385 has 24 divisors (see below), whose sum is σ = 447356520. Its totient is φ = 136568832.

The previous prime is 257078321. The next prime is 257078387. The reversal of 257078385 is 583870752.

257078385 is a `hidden beast` number, since 2 + 570 + 78 + 3 + 8 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 66389904 + 190688481 = 8148^2 + 13809^2 .

It is not a de Polignac number, because 257078385 - 2⁶ = 257078321 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 257078385.

It is not an unprimeable number, because it can be changed into a prime (257078387) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 451 + ... + 22679.

It is an arithmetic number, because the mean of its divisors is an integer number (18639855).

Almost surely, 2^257078385 is an apocalyptic number.

It is an amenable number.

257078385 is a deficient number, since it is larger than the sum of its proper divisors (190278135).

257078385 is a wasteful number, since it uses less digits than its factorization.

257078385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22497 (or 22494 counting only the distinct ones).

The product of its (nonzero) digits is 470400, while the sum is 45.

The square root of 257078385 is about 16033.6641164769. The cubic root of 257078385 is about 635.8507496583.

The spelling of 257078385 in words is "two hundred fifty-seven million, seventy-eight thousand, three hundred eighty-five".