256758240 has 48 divisors (see below), whose sum is σ = 808789968. Its totient is φ = 68468736.

The previous prime is 256758239. The next prime is 256758247. The reversal of 256758240 is 42857652.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256758247) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 266977 + ... + 267936.

It is an arithmetic number, because the mean of its divisors is an integer number (16849791).

Almost surely, 2^256758240 is an apocalyptic number.

256758240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256758240 is an abundant number, since it is smaller than the sum of its proper divisors (552031728).

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

256758240 is a wasteful number, since it uses less digits than its factorization.

256758240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 534931 (or 534923 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 39.

The square root of 256758240 is about 16023.6774805286. The cubic root of 256758240 is about 635.5866940114.

The spelling of 256758240 in words is "two hundred fifty-six million, seven hundred fifty-eight thousand, two hundred forty".