257984 has 28 divisors (see below), whose sum is σ = 533400. Its totient is φ = 123648.

The previous prime is 257981. The next prime is 257987. The reversal of 257984 is 489752.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (257981) and next prime (257987).

Its product of digits (20160) is a multiple of the sum of its prime factors (180).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1787 + ... + 1925.

It is an arithmetic number, because the mean of its divisors is an integer number (19050).

2²⁵⁷⁹⁸⁴ 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 257984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (266700).

257984 is an abundant number, since it is smaller than the sum of its proper divisors (275416).

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

257984 is a wasteful number, since it uses less digits than its factorization.

257984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180 (or 170 counting only the distinct ones).

The product of its digits is 20160, while the sum is 35.

The square root of 257984 is about 507.9212537392. The cubic root of 257984 is about 63.6596515880.

The spelling of 257984 in words is "two hundred fifty-seven thousand, nine hundred eighty-four".