256433856 has 168 divisors, whose sum is σ = 800228016. Its totient is φ = 72253440.

The previous prime is 256433851. The next prime is 256433867. The reversal of 256433856 is 658334652.

256433856 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (168).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (256433851) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 912436 + ... + 912716.

It is an arithmetic number, because the mean of its divisors is an integer number (4763262).

Almost surely, 2^256433856 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 256433856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (400114008).

256433856 is an abundant number, since it is smaller than the sum of its proper divisors (543794160).

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

256433856 is a wasteful number, since it uses less digits than its factorization.

256433856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407 (or 390 counting only the distinct ones).

The product of its digits is 518400, while the sum is 42.

The square root of 256433856 is about 16013.5522605073. The cubic root of 256433856 is about 635.3189180668.

The spelling of 256433856 in words is "two hundred fifty-six million, four hundred thirty-three thousand, eight hundred fifty-six".