256006928640 has 144 divisors (see below), whose sum is σ = 819293380416. Its totient is φ = 68128972800.

The previous prime is 256006928627. The next prime is 256006928689. The reversal of 256006928640 is 46829600652.

It is a happy number.

256006928640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 256006928640.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1817550 + ... + 1953330.

It is an arithmetic number, because the mean of its divisors is an integer number (5689537364).

Almost surely, 2^256006928640 is an apocalyptic number.

256006928640 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 256006928640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (409646690208).

256006928640 is an abundant number, since it is smaller than the sum of its proper divisors (563286451776).

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

256006928640 is a wasteful number, since it uses less digits than its factorization.

256006928640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136296 (or 136282 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 48.

The spelling of 256006928640 in words is "two hundred fifty-six billion, six million, nine hundred twenty-eight thousand, six hundred forty".