280138960 has 40 divisors (see below), whose sum is σ = 660259080. Its totient is φ = 110518272.

The previous prime is 280138931. The next prime is 280139053. The reversal of 280138960 is 69831082.

It can be written as a sum of positive squares in 4 ways, for example, as 63107136 + 217031824 = 7944^2 + 14732^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 18145 + ... + 29824.

It is an arithmetic number, because the mean of its divisors is an integer number (16506477).

Almost surely, 2^280138960 is an apocalyptic number.

280138960 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

280138960 is an abundant number, since it is smaller than the sum of its proper divisors (380120120).

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

280138960 is a wasteful number, since it uses less digits than its factorization.

280138960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48055 (or 48049 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 280138960 is about 16737.3522398257. The cubic root of 280138960 is about 654.3214697044.

The spelling of 280138960 in words is "two hundred eighty million, one hundred thirty-eight thousand, nine hundred sixty".