280991004 has 96 divisors (see below), whose sum is σ = 773799936. Its totient is φ = 77699520.

The previous prime is 280991003. The next prime is 280991017. The reversal of 280991004 is 400199082.

280991004 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280991003) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 406299 + ... + 406989.

It is an arithmetic number, because the mean of its divisors is an integer number (8060416).

Almost surely, 2^280991004 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 280991004, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (386899968).

280991004 is an abundant number, since it is smaller than the sum of its proper divisors (492808932).

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

280991004 is a wasteful number, since it uses less digits than its factorization.

280991004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 855 (or 853 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 280991004 is about 16762.7862839088. The cubic root of 280991004 is about 654.9841722570.

The spelling of 280991004 in words is "two hundred eighty million, nine hundred ninety-one thousand, four".