289321 has 4 divisors (see below), whose sum is σ = 290500. Its totient is φ = 288144.

The previous prime is 289319. The next prime is 289343. The reversal of 289321 is 123982.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 123982 = 2 ⋅61991.

It can be written as a sum of positive squares in 2 ways, for example, as 190096 + 99225 = 436^2 + 315^2 .

It is a cyclic number.

It is not a de Polignac number, because 289321 - 2¹ = 289319 is a prime.

It is a Duffinian number.

289321 is a lucky number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 289321.

It is not an unprimeable number, because it can be changed into a prime (289361) 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, 66 + ... + 763.

It is an arithmetic number, because the mean of its divisors is an integer number (72625).

2²⁸⁹³²¹ is an apocalyptic number.

It is an amenable number.

289321 is a deficient number, since it is larger than the sum of its proper divisors (1179).

289321 is an equidigital number, since it uses as much as digits as its factorization.

289321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1178.

The product of its digits is 864, while the sum is 25.

The square root of 289321 is about 537.8856755854. The cubic root of 289321 is about 66.1393596505.

The spelling of 289321 in words is "two hundred eighty-nine thousand, three hundred twenty-one".