256415040 has 504 divisors, whose sum is σ = 1084112640. Its totient is φ = 55351296.

The previous prime is 256415021. The next prime is 256415059. The reversal of 256415040 is 40514652.

It is an interprime number because it is at equal distance from previous prime (256415021) and next prime (256415059).

It is a tau number, because it is divible by the number of its divisors (504).

It is a junction number, because it is equal to n+sod(n) for n = 256414995 and 256415013.

It is a congruent number.

It is an unprimeable number.

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 71 ways as a sum of consecutive naturals, for example, 3245721 + ... + 3245799.

Almost surely, 2^256415040 is an apocalyptic number.

256415040 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 256415040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (542056320).

256415040 is an abundant number, since it is smaller than the sum of its proper divisors (827697600).

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

256415040 is a wasteful number, since it uses less digits than its factorization.

256415040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 256415040 is about 16012.9647473539. The cubic root of 256415040 is about 635.3033787079.

Adding to 256415040 its reverse (40514652), we get a palindrome (296929692).

The spelling of 256415040 in words is "two hundred fifty-six million, four hundred fifteen thousand, forty".