256157440 has 288 divisors, whose sum is σ = 805303296. Its totient is φ = 75694080.

The previous prime is 256157437. The next prime is 256157441. The reversal of 256157440 is 44751652.

It is a junction number, because it is equal to n+sod(n) for n = 256157396 and 256157405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256157441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2266824 + ... + 2266936.

It is an arithmetic number, because the mean of its divisors is an integer number (2796192).

Almost surely, 2^256157440 is an apocalyptic number.

256157440 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 256157440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (402651648).

256157440 is an abundant number, since it is smaller than the sum of its proper divisors (549145856).

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

256157440 is a wasteful number, since it uses less digits than its factorization.

256157440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 34.

The square root of 256157440 is about 16004.9192437825. The cubic root of 256157440 is about 635.0905609984.

The spelling of 256157440 in words is "two hundred fifty-six million, one hundred fifty-seven thousand, four hundred forty".