280404009 has 6 divisors (see below), whose sum is σ = 405028026. Its totient is φ = 186936000.

The previous prime is 280403993. The next prime is 280404029. The reversal of 280404009 is 900404082.

It can be written as a sum of positive squares in only one way, i.e., 252810000 + 27594009 = 15900^2 + 5253^2 .

It is not a de Polignac number, because 280404009 - 2⁴ = 280403993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (280404029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 15577992 + ... + 15578009.

It is an arithmetic number, because the mean of its divisors is an integer number (67504671).

Almost surely, 2^280404009 is an apocalyptic number.

It is an amenable number.

280404009 is a deficient number, since it is larger than the sum of its proper divisors (124624017).

280404009 is a wasteful number, since it uses less digits than its factorization.

280404009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31156007 (or 31156004 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 280404009 is about 16745.2682570331. The cubic root of 280404009 is about 654.5277632582.

The spelling of 280404009 in words is "two hundred eighty million, four hundred four thousand, nine".