280879240 has 16 divisors (see below), whose sum is σ = 631978380. Its totient is φ = 112351680.

The previous prime is 280879237. The next prime is 280879259. The reversal of 280879240 is 42978082.

It can be written as a sum of positive squares in 2 ways, for example, as 276823044 + 4056196 = 16638^2 + 2014^2 .

It is a Harshad number since it is a multiple of its sum of digits (40), and also a Moran number because the ratio is a prime number: 7021981 = 280879240 / (2 + 8 + 0 + 8 + 7 + 9 + 2 + 4 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 280879193 and 280879202.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3510951 + ... + 3511030.

Almost surely, 2^280879240 is an apocalyptic number.

280879240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

280879240 is an abundant number, since it is smaller than the sum of its proper divisors (351099140).

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

280879240 is a wasteful number, since it uses less digits than its factorization.

280879240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7021992 (or 7021988 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 280879240 is about 16759.4522583526. The cubic root of 280879240 is about 654.8973208897.

The spelling of 280879240 in words is "two hundred eighty million, eight hundred seventy-nine thousand, two hundred forty".