258065661 has 32 divisors (see below), whose sum is σ = 426083328. Its totient is φ = 135555840.

The previous prime is 258065569. The next prime is 258065699. The reversal of 258065661 is 166560852.

It is not a de Polignac number, because 258065661 - 2⁹ = 258065149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (258065261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6946 + ... + 23756.

It is an arithmetic number, because the mean of its divisors is an integer number (13315104).

Almost surely, 2^258065661 is an apocalyptic number.

258065661 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

258065661 is a deficient number, since it is larger than the sum of its proper divisors (168017667).

258065661 is a wasteful number, since it uses less digits than its factorization.

258065661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16881.

The product of its (nonzero) digits is 86400, while the sum is 39.

The square root of 258065661 is about 16064.4222118320. The cubic root of 258065661 is about 636.6636771817.

The spelling of 258065661 in words is "two hundred fifty-eight million, sixty-five thousand, six hundred sixty-one".