256445280 has 576 divisors, whose sum is σ = 1144765440. Its totient is φ = 50761728.

The previous prime is 256445279. The next prime is 256445291. The reversal of 256445280 is 82544652.

It is a happy number.

256445280 is a `hidden beast` number, since 2 + 5 + 644 + 5 + 2 + 8 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2489709 + ... + 2489811.

It is an arithmetic number, because the mean of its divisors is an integer number (1987440).

Almost surely, 2^256445280 is an apocalyptic number.

256445280 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 256445280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (572382720).

256445280 is an abundant number, since it is smaller than the sum of its proper divisors (888320160).

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

256445280 is a wasteful number, since it uses less digits than its factorization.

256445280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163 (or 152 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 36.

The square root of 256445280 is about 16013.9089544059. The cubic root of 256445280 is about 635.3283523067.

The spelling of 256445280 in words is "two hundred fifty-six million, four hundred forty-five thousand, two hundred eighty".