280780560 has 160 divisors (see below), whose sum is σ = 983448960. Its totient is φ = 73612800.

The previous prime is 280780543. The next prime is 280780561. The reversal of 280780560 is 65087082.

280780560 is a `hidden beast` number, since 28 + 0 + 78 + 0 + 560 = 666.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

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 (280780561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 130695 + ... + 132825.

It is an arithmetic number, because the mean of its divisors is an integer number (6146556).

Almost surely, 2^280780560 is an apocalyptic number.

280780560 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 280780560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (491724480).

280780560 is an abundant number, since it is smaller than the sum of its proper divisors (702668400).

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

280780560 is a wasteful number, since it uses less digits than its factorization.

280780560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2214 (or 2202 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 280780560 is about 16756.5079894350. The cubic root of 280780560 is about 654.8206178942.

The spelling of 280780560 in words is "two hundred eighty million, seven hundred eighty thousand, five hundred sixty".