257657345 has 16 divisors (see below), whose sum is σ = 337763520. Its totient is φ = 187128000.

The previous prime is 257657341. The next prime is 257657353. The reversal of 257657345 is 543756752.

It is not a de Polignac number, because 257657345 - 2² = 257657341 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 257657296 and 257657305.

It is not an unprimeable number, because it can be changed into a prime (257657341) 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 15 ways as a sum of consecutive naturals, for example, 42770 + ... + 48420.

It is an arithmetic number, because the mean of its divisors is an integer number (21110220).

Almost surely, 2^257657345 is an apocalyptic number.

It is an amenable number.

257657345 is a deficient number, since it is larger than the sum of its proper divisors (80106175).

257657345 is a wasteful number, since it uses less digits than its factorization.

257657345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6496.

The product of its digits is 882000, while the sum is 44.

The square root of 257657345 is about 16051.7084760470. The cubic root of 257657345 is about 636.3277198004.

The spelling of 257657345 in words is "two hundred fifty-seven million, six hundred fifty-seven thousand, three hundred forty-five".