257760 has 72 divisors (see below), whose sum is σ = 884520. Its totient is φ = 68352.

The previous prime is 257731. The next prime is 257783. The reversal of 257760 is 67752.

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

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

257760 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 11 ways as a sum of consecutive naturals, for example, 1351 + ... + 1529.

It is an arithmetic number, because the mean of its divisors is an integer number (12285).

2²⁵⁷⁷⁶⁰ is an apocalyptic number.

257760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 257760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (442260).

257760 is an abundant number, since it is smaller than the sum of its proper divisors (626760).

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

257760 is a wasteful number, since it uses less digits than its factorization.

257760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200 (or 189 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 27.

The square root of 257760 is about 507.7006992313. The cubic root of 257760 is about 63.6412216452.

The spelling of 257760 in words is "two hundred fifty-seven thousand, seven hundred sixty".