258851856681 has 64 divisors (see below), whose sum is σ = 420456349440. Its totient is φ = 156090654720.

The previous prime is 258851856661. The next prime is 258851856709. The reversal of 258851856681 is 186658158852.

It is a happy number.

258851856681 is a `hidden beast` number, since 2 + 5 + 8 + 8 + 518 + 56 + 68 + 1 = 666.

It is not a de Polignac number, because 258851856681 - 2¹¹ = 258851854633 is a prime.

It is a super-2 number, since 2×258851856681² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (258851856661) 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 63 ways as a sum of consecutive naturals, for example, 57354681 + ... + 57359193.

It is an arithmetic number, because the mean of its divisors is an integer number (6569630460).

Almost surely, 2^258851856681 is an apocalyptic number.

It is an amenable number.

258851856681 is a deficient number, since it is larger than the sum of its proper divisors (161604492759).

258851856681 is a wasteful number, since it uses less digits than its factorization.

258851856681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5463 (or 5457 counting only the distinct ones).

The product of its digits is 36864000, while the sum is 63.

The spelling of 258851856681 in words is "two hundred fifty-eight billion, eight hundred fifty-one million, eight hundred fifty-six thousand, six hundred eighty-one".