280391240 has 32 divisors (see below), whose sum is σ = 631445760. Its totient is φ = 112056000.

The previous prime is 280391239. The next prime is 280391257. The reversal of 280391240 is 42193082.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 55625 + ... + 60455.

It is an arithmetic number, because the mean of its divisors is an integer number (19732680).

Almost surely, 2^280391240 is an apocalyptic number.

280391240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

280391240 is an abundant number, since it is smaller than the sum of its proper divisors (351054520).

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

280391240 is a wasteful number, since it uses less digits than its factorization.

280391240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6293 (or 6289 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 280391240 is about 16744.8869808070. The cubic root of 280391240 is about 654.5178278416.

The spelling of 280391240 in words is "two hundred eighty million, three hundred ninety-one thousand, two hundred forty".