280870640 has 20 divisors (see below), whose sum is σ = 653024424. Its totient is φ = 112348224.

The previous prime is 280870627. The next prime is 280870669. The reversal of 280870640 is 46078082.

280870640 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (20).

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 280870640.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1755362 + ... + 1755521.

Almost surely, 2^280870640 is an apocalyptic number.

280870640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

280870640 is an abundant number, since it is smaller than the sum of its proper divisors (372153784).

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

280870640 is a wasteful number, since it uses less digits than its factorization.

280870640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3510896 (or 3510890 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 35.

The square root of 280870640 is about 16759.1956847577. The cubic root of 280870640 is about 654.8906369088.

The spelling of 280870640 in words is "two hundred eighty million, eight hundred seventy thousand, six hundred forty".