257391249 has 16 divisors (see below), whose sum is σ = 351671232. Its totient is φ = 167364288.

The previous prime is 257391241. The next prime is 257391263. The reversal of 257391249 is 942193752.

It is not a de Polignac number, because 257391249 - 2³ = 257391241 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 257391249.

It is not an unprimeable number, because it can be changed into a prime (257391241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 158767 + ... + 160379.

It is an arithmetic number, because the mean of its divisors is an integer number (21979452).

Almost surely, 2^257391249 is an apocalyptic number.

It is an amenable number.

257391249 is a deficient number, since it is larger than the sum of its proper divisors (94279983).

257391249 is a wasteful number, since it uses less digits than its factorization.

257391249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2896.

The product of its digits is 136080, while the sum is 42.

The square root of 257391249 is about 16043.4176221901. The cubic root of 257391249 is about 636.1085882190.

The spelling of 257391249 in words is "two hundred fifty-seven million, three hundred ninety-one thousand, two hundred forty-nine".