280781056 has 72 divisors (see below), whose sum is σ = 598973760. Its totient is φ = 131045376.

The previous prime is 280781051. The next prime is 280781071. The reversal of 280781056 is 650187082.

It is not an unprimeable number, because it can be changed into a prime (280781051) 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, 252630 + ... + 253738.

It is an arithmetic number, because the mean of its divisors is an integer number (8319080).

Almost surely, 2^280781056 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 280781056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (299486880).

280781056 is an abundant number, since it is smaller than the sum of its proper divisors (318192704).

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

280781056 is a wasteful number, since it uses less digits than its factorization.

280781056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1191 (or 1177 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 37.

The square root of 280781056 is about 16756.5227896482. The cubic root of 280781056 is about 654.8210034750.

The spelling of 280781056 in words is "two hundred eighty million, seven hundred eighty-one thousand, fifty-six".