257966839278 has 12 divisors (see below), whose sum is σ = 558928151808. Its totient is φ = 85988946420.

The previous prime is 257966839253. The next prime is 257966839283. The reversal of 257966839278 is 872938669752.

257966839278 is a `hidden beast` number, since 25 + 7 + 96 + 68 + 392 + 78 = 666.

It is a super-2 number, since 2×257966839278² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 7165745518 + ... + 7165745553.

It is an arithmetic number, because the mean of its divisors is an integer number (46577345984).

Almost surely, 2^257966839278 is an apocalyptic number.

257966839278 is an abundant number, since it is smaller than the sum of its proper divisors (300961312530).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

257966839278 is a wasteful number, since it uses less digits than its factorization.

257966839278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14331491079 (or 14331491076 counting only the distinct ones).

The product of its digits is 548674560, while the sum is 72.

The spelling of 257966839278 in words is "two hundred fifty-seven billion, nine hundred sixty-six million, eight hundred thirty-nine thousand, two hundred seventy-eight".