256320 has 84 divisors (see below), whose sum is σ = 891540. Its totient is φ = 67584.

The previous prime is 256313. The next prime is 256337. The reversal of 256320 is 23652.

It can be written as a sum of positive squares in 2 ways, for example, as 69696 + 186624 = 264^2 + 432^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nialpdrome in base 4.

It is a zygodrome in base 4.

It is a junction number, because it is equal to n+sod(n) for n = 256293 and 256302.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2836 + ... + 2924.

2²⁵⁶³²⁰ is an apocalyptic number.

256320 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 256320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (445770).

256320 is an abundant number, since it is smaller than the sum of its proper divisors (635220).

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

256320 is a wasteful number, since it uses less digits than its factorization.

256320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112 (or 99 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 256320 is about 506.2805546335. The cubic root of 256320 is about 63.5224877470.

Adding to 256320 its reverse (23652), we get a palindrome (279972).

It can be divided in two parts, 256 and 320, that added together give a square (576 = 24²).

The spelling of 256320 in words is "two hundred fifty-six thousand, three hundred twenty".