257646967925 has 6 divisors (see below), whose sum is σ = 319482240258. Its totient is φ = 206117574320.

The previous prime is 257646967901. The next prime is 257646967933. The reversal of 257646967925 is 529769646752.

It can be written as a sum of positive squares in 3 ways, for example, as 33859312081 + 223787655844 = 184009^2 + 473062^2 .

It is not a de Polignac number, because 257646967925 - 2²² = 257642773621 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5152939334 + ... + 5152939383.

It is an arithmetic number, because the mean of its divisors is an integer number (53247040043).

Almost surely, 2^257646967925 is an apocalyptic number.

257646967925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

257646967925 is a deficient number, since it is larger than the sum of its proper divisors (61835272333).

257646967925 is a wasteful number, since it uses less digits than its factorization.

257646967925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10305878727 (or 10305878722 counting only the distinct ones).

The product of its digits is 342921600, while the sum is 68.

The spelling of 257646967925 in words is "two hundred fifty-seven billion, six hundred forty-six million, nine hundred sixty-seven thousand, nine hundred twenty-five".