257731968 has 128 divisors (see below), whose sum is σ = 780887520. Its totient is φ = 74612736.

The previous prime is 257731967. The next prime is 257732009. The reversal of 257731968 is 869137752.

257731968 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257731967) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83346 + ... + 86382.

Almost surely, 2^257731968 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 257731968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (390443760).

257731968 is an abundant number, since it is smaller than the sum of its proper divisors (523155552).

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

257731968 is a wasteful number, since it uses less digits than its factorization.

257731968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3084 (or 3072 counting only the distinct ones).

The product of its digits is 635040, while the sum is 48.

The square root of 257731968 is about 16054.0327643866. The cubic root of 257731968 is about 636.3891451791.

The spelling of 257731968 in words is "two hundred fifty-seven million, seven hundred thirty-one thousand, nine hundred sixty-eight".