256520 has 48 divisors (see below), whose sum is σ = 646380. Its totient is φ = 91520.

The previous prime is 256517. The next prime is 256541. The reversal of 256520 is 25652.

It is a happy number.

256520 is nontrivially palindromic in base 15.

256520 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 256036 + 484 = 506^2 + 22^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 256492 and 256501.

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, 4814 + ... + 4866.

2²⁵⁶⁵²⁰ is an apocalyptic number.

256520 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 256520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (323190).

256520 is an abundant number, since it is smaller than the sum of its proper divisors (389860).

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

256520 is a wasteful number, since it uses less digits than its factorization.

256520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86 (or 71 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 256520 is about 506.4780350617. The cubic root of 256520 is about 63.5390051141.

The spelling of 256520 in words is "two hundred fifty-six thousand, five hundred twenty".