280445 has 8 divisors (see below), whose sum is σ = 367200. Its totient is φ = 203920.

The previous prime is 280411. The next prime is 280451. The reversal of 280445 is 544082.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 280445 - 2¹⁰ = 279421 is a prime.

It is a Curzon number.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 280445.

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, 2495 + ... + 2604.

It is an arithmetic number, because the mean of its divisors is an integer number (45900).

2²⁸⁰⁴⁴⁵ is an apocalyptic number.

It is an amenable number.

280445 is a deficient number, since it is larger than the sum of its proper divisors (86755).

280445 is a wasteful number, since it uses less digits than its factorization.

280445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5115.

The product of its (nonzero) digits is 1280, while the sum is 23.

The square root of 280445 is about 529.5705807539. The cubic root of 280445 is about 65.4559655860.

The spelling of 280445 in words is "two hundred eighty thousand, four hundred forty-five".