258605861 has 2 divisors, whose sum is σ = 258605862. Its totient is φ = 258605860.

The previous prime is 258605849. The next prime is 258605917. The reversal of 258605861 is 168506852.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 256992961 + 1612900 = 16031^2 + 1270^2 .

It is a cyclic number.

It is not a de Polignac number, because 258605861 - 2¹⁸ = 258343717 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (258605801) 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 as a sum of consecutive naturals, namely, 129302930 + 129302931.

It is an arithmetic number, because the mean of its divisors is an integer number (129302931).

Almost surely, 2^258605861 is an apocalyptic number.

It is an amenable number.

258605861 is a deficient number, since it is larger than the sum of its proper divisors (1).

258605861 is an equidigital number, since it uses as much as digits as its factorization.

258605861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 115200, while the sum is 41.

The square root of 258605861 is about 16081.2269743325. The cubic root of 258605861 is about 637.1076029896.

Subtracting from 258605861 its reverse (168506852), we obtain a palindrome (90099009).

The spelling of 258605861 in words is "two hundred fifty-eight million, six hundred five thousand, eight hundred sixty-one".