257693864 has 8 divisors (see below), whose sum is σ = 483176010. Its totient is φ = 128846928.

The previous prime is 257693833. The next prime is 257693879. The reversal of 257693864 is 468396752.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 257345764 + 348100 = 16042^2 + 590^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×257693864² = 132812255086500992, which contains 22 as substring.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 16105859 + ... + 16105874.

Almost surely, 2^257693864 is an apocalyptic number.

It is an amenable number.

257693864 is a deficient number, since it is larger than the sum of its proper divisors (225482146).

257693864 is a wasteful number, since it uses less digits than its factorization.

257693864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32211739 (or 32211735 counting only the distinct ones).

The product of its digits is 2177280, while the sum is 50.

The square root of 257693864 is about 16052.8459782059. The cubic root of 257693864 is about 636.3577816307.

The spelling of 257693864 in words is "two hundred fifty-seven million, six hundred ninety-three thousand, eight hundred sixty-four".