256281680 has 40 divisors (see below), whose sum is σ = 598120200. Its totient is φ = 102123008.

The previous prime is 256281643. The next prime is 256281689. The reversal of 256281680 is 86182652.

256281680 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 153664 + 256128016 = 392^2 + 16004^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256281689) 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, 15566 + ... + 27474.

It is an arithmetic number, because the mean of its divisors is an integer number (14953005).

Almost surely, 2^256281680 is an apocalyptic number.

256281680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256281680 is an abundant number, since it is smaller than the sum of its proper divisors (341838520).

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

256281680 is a wasteful number, since it uses less digits than its factorization.

256281680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12191 (or 12185 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 38.

The square root of 256281680 is about 16008.8000799560. The cubic root of 256281680 is about 635.1932203867.

The spelling of 256281680 in words is "two hundred fifty-six million, two hundred eighty-one thousand, six hundred eighty".