280889 has 4 divisors (see below), whose sum is σ = 321024. Its totient is φ = 240756.

The previous prime is 280883. The next prime is 280897. The reversal of 280889 is 988082.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 988082 = 2 ⋅494041.

It is a cyclic number.

It is not a de Polignac number, because 280889 - 2¹⁶ = 215353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (280883) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20057 + ... + 20070.

It is an arithmetic number, because the mean of its divisors is an integer number (80256).

2²⁸⁰⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

280889 is a deficient number, since it is larger than the sum of its proper divisors (40135).

280889 is an equidigital number, since it uses as much as digits as its factorization.

280889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40134.

The product of its (nonzero) digits is 9216, while the sum is 35.

The square root of 280889 is about 529.9896225399. The cubic root of 280889 is about 65.4904906266.

The spelling of 280889 in words is "two hundred eighty thousand, eight hundred eighty-nine".