280728816 has 40 divisors (see below), whose sum is σ = 750227280. Its totient is φ = 90349056.

The previous prime is 280728797. The next prime is 280728829. The reversal of 280728816 is 618827082.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 99445 + ... + 102228.

It is an arithmetic number, because the mean of its divisors is an integer number (18755682).

Almost surely, 2^280728816 is an apocalyptic number.

It is an amenable number.

280728816 is an abundant number, since it is smaller than the sum of its proper divisors (469498464).

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

280728816 is a wasteful number, since it uses less digits than its factorization.

280728816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201713 (or 201707 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 42.

The square root of 280728816 is about 16754.9639211787. The cubic root of 280728816 is about 654.7803906082.

The spelling of 280728816 in words is "two hundred eighty million, seven hundred twenty-eight thousand, eight hundred sixteen".