280664813 has 16 divisors (see below), whose sum is σ = 341107200. Its totient is φ = 227398080.

The previous prime is 280664807. The next prime is 280664821. The reversal of 280664813 is 318466082.

It is a happy number.

It is not a de Polignac number, because 280664813 - 2¹² = 280660717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280664873) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29693 + ... + 37986.

It is an arithmetic number, because the mean of its divisors is an integer number (21319200).

Almost surely, 2^280664813 is an apocalyptic number.

It is an amenable number.

280664813 is a deficient number, since it is larger than the sum of its proper divisors (60442387).

280664813 is a wasteful number, since it uses less digits than its factorization.

280664813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67732.

The product of its (nonzero) digits is 55296, while the sum is 38.

The square root of 280664813 is about 16753.0538410166. The cubic root of 280664813 is about 654.7306259810.

The spelling of 280664813 in words is "two hundred eighty million, six hundred sixty-four thousand, eight hundred thirteen".