289723 has 4 divisors (see below), whose sum is σ = 331120. Its totient is φ = 248328.

The previous prime is 289721. The next prime is 289727. The reversal of 289723 is 327982.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 327982 = 2 ⋅163991.

It is a cyclic number.

It is not a de Polignac number, because 289723 - 2¹ = 289721 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (289721) 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, 20688 + ... + 20701.

It is an arithmetic number, because the mean of its divisors is an integer number (82780).

2²⁸⁹⁷²³ is an apocalyptic number.

289723 is a deficient number, since it is larger than the sum of its proper divisors (41397).

289723 is an equidigital number, since it uses as much as digits as its factorization.

289723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41396.

The product of its digits is 6048, while the sum is 31.

The square root of 289723 is about 538.2592312260. The cubic root of 289723 is about 66.1699781420.

The spelling of 289723 in words is "two hundred eighty-nine thousand, seven hundred twenty-three".