256957409280 has 768 divisors, whose sum is σ = 999578361600. Its totient is φ = 55490641920.

The previous prime is 256957409273. The next prime is 256957409327. The reversal of 256957409280 is 82904759652.

256957409280 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 (768).

It is a super-2 number, since 2×256957409280² (a number of 24 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 256957409280.

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 63 ways as a sum of consecutive naturals, for example, 127394832 + ... + 127396848.

It is an arithmetic number, because the mean of its divisors is an integer number (1301534325).

Almost surely, 2^256957409280 is an apocalyptic number.

256957409280 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 256957409280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (499789180800).

256957409280 is an abundant number, since it is smaller than the sum of its proper divisors (742620952320).

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

256957409280 is a wasteful number, since it uses less digits than its factorization.

256957409280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2100 (or 2080 counting only the distinct ones).

The product of its (nonzero) digits is 10886400, while the sum is 57.

The spelling of 256957409280 in words is "two hundred fifty-six billion, nine hundred fifty-seven million, four hundred nine thousand, two hundred eighty".