280897812 has 72 divisors (see below), whose sum is σ = 768298440. Its totient is φ = 86019840.

The previous prime is 280897811. The next prime is 280897819. The reversal of 280897812 is 218798082.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 98485776 + 182412036 = 9924^2 + 13506^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280897811) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 105862 + ... + 108482.

Almost surely, 2^280897812 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 280897812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (384149220).

280897812 is an abundant number, since it is smaller than the sum of its proper divisors (487400628).

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

280897812 is a wasteful number, since it uses less digits than its factorization.

280897812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2873 (or 2868 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The square root of 280897812 is about 16760.0063245811. The cubic root of 280897812 is about 654.9117547142.

The spelling of 280897812 in words is "two hundred eighty million, eight hundred ninety-seven thousand, eight hundred twelve".