257791968 has 72 divisors (see below), whose sum is σ = 837830448. Its totient is φ = 73654272.

The previous prime is 257791967. The next prime is 257791999. The reversal of 257791968 is 869197752.

257791968 is a `hidden beast` number, since 2 + 577 + 9 + 1 + 9 + 68 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257791967) 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 11 ways as a sum of consecutive naturals, for example, 61921 + ... + 65952.

It is an arithmetic number, because the mean of its divisors is an integer number (11636534).

Almost surely, 2^257791968 is an apocalyptic number.

257791968 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

257791968 is an abundant number, since it is smaller than the sum of its proper divisors (580038480).

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

257791968 is a wasteful number, since it uses less digits than its factorization.

257791968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127896 (or 127885 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 54.

The square root of 257791968 is about 16055.9013449884. The cubic root of 257791968 is about 636.4385251433.

The spelling of 257791968 in words is "two hundred fifty-seven million, seven hundred ninety-one thousand, nine hundred sixty-eight".