256359978 has 80 divisors (see below), whose sum is σ = 685111680. Its totient is φ = 70053984.

The previous prime is 256359931. The next prime is 256359979. The reversal of 256359978 is 879953652.

256359978 is a `hidden beast` number, since 2 + 563 + 5 + 9 + 9 + 78 = 666.

256359978 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256359979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 21168 + ... + 30996.

It is an arithmetic number, because the mean of its divisors is an integer number (8563896).

Almost surely, 2^256359978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256359978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (342555840).

256359978 is an abundant number, since it is smaller than the sum of its proper divisors (428751702).

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

256359978 is a wasteful number, since it uses less digits than its factorization.

256359978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9873 (or 9864 counting only the distinct ones).

The product of its digits is 4082400, while the sum is 54.

The square root of 256359978 is about 16011.2453606832. The cubic root of 256359978 is about 635.2579009038.

The spelling of 256359978 in words is "two hundred fifty-six million, three hundred fifty-nine thousand, nine hundred seventy-eight".