258643665 has 32 divisors (see below), whose sum is σ = 525500160. Its totient is φ = 118236672.

The previous prime is 258643643. The next prime is 258643681. The reversal of 258643665 is 566346852.

258643665 is a `hidden beast` number, since 2 + 586 + 4 + 3 + 6 + 65 = 666.

It is not a de Polignac number, because 258643665 - 2⁶ = 258643601 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 258643665.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 135904 + ... + 137793.

It is an arithmetic number, because the mean of its divisors is an integer number (16421880).

Almost surely, 2^258643665 is an apocalyptic number.

It is an amenable number.

258643665 is an abundant number, since it is smaller than the sum of its proper divisors (266856495).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

258643665 is a wasteful number, since it uses less digits than its factorization.

258643665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273718 (or 273712 counting only the distinct ones).

The product of its digits is 1036800, while the sum is 45.

The square root of 258643665 is about 16082.4023392029. The cubic root of 258643665 is about 637.1386464240.

The spelling of 258643665 in words is "two hundred fifty-eight million, six hundred forty-three thousand, six hundred sixty-five".