256842840 has 64 divisors (see below), whose sum is σ = 804038400. Its totient is φ = 65512832.

The previous prime is 256842809. The next prime is 256842841. The reversal of 256842840 is 48248652.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256842841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43770 + ... + 49289.

It is an arithmetic number, because the mean of its divisors is an integer number (12563100).

Almost surely, 2^256842840 is an apocalyptic number.

256842840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256842840 is an abundant number, since it is smaller than the sum of its proper divisors (547195560).

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

256842840 is a wasteful number, since it uses less digits than its factorization.

256842840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93096 (or 93092 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 39.

The square root of 256842840 is about 16026.3171065594. The cubic root of 256842840 is about 635.6564934327.

The spelling of 256842840 in words is "two hundred fifty-six million, eight hundred forty-two thousand, eight hundred forty".