280863 has 12 divisors (see below), whose sum is σ = 442728. Its totient is φ = 170160.

The previous prime is 280859. The next prime is 280871. The reversal of 280863 is 368082.

It is not a de Polignac number, because 280863 - 2² = 280859 is a prime.

It is an Ulam number.

280863 is a lucky number.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280843) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1320 + ... + 1517.

It is an arithmetic number, because the mean of its divisors is an integer number (36894).

2²⁸⁰⁸⁶³ is an apocalyptic number.

280863 is a deficient number, since it is larger than the sum of its proper divisors (161865).

280863 is a wasteful number, since it uses less digits than its factorization.

280863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2854 (or 2851 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 280863 is about 529.9650931901. The cubic root of 280863 is about 65.4884698932.

The spelling of 280863 in words is "two hundred eighty thousand, eight hundred sixty-three".