258861 has 4 divisors (see below), whose sum is σ = 345152. Its totient is φ = 172572.

The previous prime is 258847. The next prime is 258871. The reversal of 258861 is 168852.

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.

It is not a de Polignac number, because 258861 - 2⁷ = 258733 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 258861.

It is not an unprimeable number, because it can be changed into a prime (258871) 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, 43141 + ... + 43146.

It is an arithmetic number, because the mean of its divisors is an integer number (86288).

2²⁵⁸⁸⁶¹ is an apocalyptic number.

It is an amenable number.

258861 is a deficient number, since it is larger than the sum of its proper divisors (86291).

258861 is an equidigital number, since it uses as much as digits as its factorization.

258861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86290.

The product of its digits is 3840, while the sum is 30.

The square root of 258861 is about 508.7838440831. The cubic root of 258861 is about 63.7317056310.

Subtracting from 258861 its reverse (168852), we obtain a palindrome (90009).

The spelling of 258861 in words is "two hundred fifty-eight thousand, eight hundred sixty-one".