257065521 has 8 divisors (see below), whose sum is σ = 343519200. Its totient is φ = 170994432.

The previous prime is 257065519. The next prime is 257065559. The reversal of 257065521 is 125560752.

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

It is not a de Polignac number, because 257065521 - 2¹ = 257065519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (257065561) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94075 + ... + 96768.

It is an arithmetic number, because the mean of its divisors is an integer number (42939900).

Almost surely, 2^257065521 is an apocalyptic number.

It is an amenable number.

257065521 is a deficient number, since it is larger than the sum of its proper divisors (86453679).

257065521 is a wasteful number, since it uses less digits than its factorization.

257065521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191295.

The product of its (nonzero) digits is 21000, while the sum is 33.

The square root of 257065521 is about 16033.2629554935. The cubic root of 257065521 is about 635.8401436578.

The spelling of 257065521 in words is "two hundred fifty-seven million, sixty-five thousand, five hundred twenty-one".