280891 has 16 divisors (see below), whose sum is σ = 338688. Its totient is φ = 230400.

The previous prime is 280883. The next prime is 280897. The reversal of 280891 is 198082.

It is a 10-Lehmer number, since φ(280891) divides (280891-1)¹⁰.

It is a cyclic number.

It is not a de Polignac number, because 280891 - 2³ = 280883 is a prime.

It is a Duffinian number.

280891 is a lucky number.

It is a plaindrome in base 12.

It is a zygodrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280897) 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, 6831 + ... + 6871.

It is an arithmetic number, because the mean of its divisors is an integer number (21168).

2²⁸⁰⁸⁹¹ is an apocalyptic number.

280891 is a deficient number, since it is larger than the sum of its proper divisors (57797).

280891 is a wasteful number, since it uses less digits than its factorization.

280891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102.

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 280891 is about 529.9915093660. The cubic root of 280891 is about 65.4906460624.

The spelling of 280891 in words is "two hundred eighty thousand, eight hundred ninety-one".