258749 has 4 divisors (see below), whose sum is σ = 259836. Its totient is φ = 257664.

The previous prime is 258743. The next prime is 258763. The reversal of 258749 is 947852.

It is a happy number.

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.

It can be written as a sum of positive squares in 2 ways, for example, as 196249 + 62500 = 443^2 + 250^2 .

It is a cyclic number.

It is not a de Polignac number, because 258749 - 2⁴ = 258733 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (258743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14 + ... + 719.

It is an arithmetic number, because the mean of its divisors is an integer number (64959).

2²⁵⁸⁷⁴⁹ is an apocalyptic number.

It is an amenable number.

258749 is a deficient number, since it is larger than the sum of its proper divisors (1087).

258749 is an equidigital number, since it uses as much as digits as its factorization.

258749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1086.

The product of its digits is 20160, while the sum is 35.

The square root of 258749 is about 508.6737657871. The cubic root of 258749 is about 63.7225128200.

The spelling of 258749 in words is "two hundred fifty-eight thousand, seven hundred forty-nine".