257547478 has 4 divisors (see below), whose sum is σ = 386321220. Its totient is φ = 128773738.

The previous prime is 257547461. The next prime is 257547481. The reversal of 257547478 is 874745752.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64386868 + ... + 64386871.

It is an arithmetic number, because the mean of its divisors is an integer number (96580305).

Almost surely, 2^257547478 is an apocalyptic number.

257547478 is a deficient number, since it is larger than the sum of its proper divisors (128773742).

257547478 is a wasteful number, since it uses less digits than its factorization.

257547478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128773741.

The product of its digits is 2195200, while the sum is 49.

The square root of 257547478 is about 16048.2858274646. The cubic root of 257547478 is about 636.2372619912.

The spelling of 257547478 in words is "two hundred fifty-seven million, five hundred forty-seven thousand, four hundred seventy-eight".