256816 has 20 divisors (see below), whose sum is σ = 568912. Its totient is φ = 110016.

The previous prime is 256813. The next prime is 256831. The reversal of 256816 is 618652.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (256813) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1035 + ... + 1258.

2²⁵⁶⁸¹⁶ is an apocalyptic number.

It is an amenable number.

256816 is an abundant number, since it is smaller than the sum of its proper divisors (312096).

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

256816 is a wasteful number, since it uses less digits than its factorization.

256816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2308 (or 2302 counting only the distinct ones).

The product of its digits is 2880, while the sum is 28.

The square root of 256816 is about 506.7701648677. The cubic root of 256816 is about 63.5634350690.

The spelling of 256816 in words is "two hundred fifty-six thousand, eight hundred sixteen".