256983440 has 60 divisors (see below), whose sum is σ = 695045916. Its totient is φ = 88107264.

The previous prime is 256983403. The next prime is 256983443. The reversal of 256983440 is 44389652.

It can be written as a sum of positive squares in 2 ways, for example, as 138956944 + 118026496 = 11788^2 + 10864^2 .

It is not an unprimeable number, because it can be changed into a prime (256983443) 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 11 ways as a sum of consecutive naturals, for example, 28859 + ... + 36698.

Almost surely, 2^256983440 is an apocalyptic number.

256983440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256983440 is an abundant number, since it is smaller than the sum of its proper divisors (438062476).

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

256983440 is a wasteful number, since it uses less digits than its factorization.

256983440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65584 (or 65571 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 41.

The square root of 256983440 is about 16030.7030413516. The cubic root of 256983440 is about 635.7724618849.

The spelling of 256983440 in words is "two hundred fifty-six million, nine hundred eighty-three thousand, four hundred forty".