280806705 has 12 divisors (see below), whose sum is σ = 486731700. Its totient is φ = 149763552.

The previous prime is 280806703. The next prime is 280806733. The reversal of 280806705 is 507608082.

It can be written as a sum of positive squares in 2 ways, for example, as 48274704 + 232532001 = 6948^2 + 15249^2 .

It is not a de Polignac number, because 280806705 - 2¹ = 280806703 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 280806705.

It is not an unprimeable number, because it can be changed into a prime (280806703) 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 11 ways as a sum of consecutive naturals, for example, 3120030 + ... + 3120119.

It is an arithmetic number, because the mean of its divisors is an integer number (40560975).

Almost surely, 2^280806705 is an apocalyptic number.

It is an amenable number.

280806705 is a deficient number, since it is larger than the sum of its proper divisors (205924995).

280806705 is a wasteful number, since it uses less digits than its factorization.

280806705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6240160 (or 6240157 counting only the distinct ones).

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

The square root of 280806705 is about 16757.2881159214. The cubic root of 280806705 is about 654.8409418958.

The spelling of 280806705 in words is "two hundred eighty million, eight hundred six thousand, seven hundred five".