257457705 has 16 divisors (see below), whose sum is σ = 413000640. Its totient is φ = 136954688.

The previous prime is 257457703. The next prime is 257457709. The reversal of 257457705 is 507754752.

It is a cyclic number.

It is not a de Polignac number, because 257457705 - 2¹ = 257457703 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (257457703) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16227 + ... + 27896.

It is an arithmetic number, because the mean of its divisors is an integer number (25812540).

Almost surely, 2^257457705 is an apocalyptic number.

It is an amenable number.

257457705 is a deficient number, since it is larger than the sum of its proper divisors (155542935).

257457705 is a wasteful number, since it uses less digits than its factorization.

257457705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44520.

The product of its (nonzero) digits is 343000, while the sum is 42.

The square root of 257457705 is about 16045.4886183002. The cubic root of 257457705 is about 636.1633292599.

The spelling of 257457705 in words is "two hundred fifty-seven million, four hundred fifty-seven thousand, seven hundred five".