256481280 has 432 divisors, whose sum is σ = 1019556720. Its totient is φ = 59473920.

The previous prime is 256481273. The next prime is 256481287. The reversal of 256481280 is 82184652.

256481280 is a `hidden beast` number, since 2 + 5 + 648 + 1 + 2 + 8 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (256481273) and next prime (256481287).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256481287) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 11151349 + ... + 11151371.

It is an arithmetic number, because the mean of its divisors is an integer number (2360085).

Almost surely, 2^256481280 is an apocalyptic number.

256481280 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 256481280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (509778360).

256481280 is an abundant number, since it is smaller than the sum of its proper divisors (763075440).

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

256481280 is a wasteful number, since it uses less digits than its factorization.

256481280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78 (or 44 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 256481280 is about 16015.0329378369. The cubic root of 256481280 is about 635.3580802217.

The spelling of 256481280 in words is "two hundred fifty-six million, four hundred eighty-one thousand, two hundred eighty".