856705507658 has 32 divisors (see below), whose sum is σ = 1725392914560. Its totient is φ = 308105876160.

The previous prime is 856705507639. The next prime is 856705507661.

856705507658 is nontrivially palindromic in base 10.

It is a Smith number, since the sum of its digits (62) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 856705507658.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 213960413 + ... + 213964416.

It is an arithmetic number, because the mean of its divisors is an integer number (53918528580).

Almost surely, 2^856705507658 is an apocalyptic number.

856705507658 is an abundant number, since it is smaller than the sum of its proper divisors (868687406902).

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

856705507658 is a wasteful number, since it uses less digits than its factorization.

856705507658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 427924862.

The product of its (nonzero) digits is 70560000, while the sum is 62.

The spelling of 856705507658 in words is "eight hundred fifty-six billion, seven hundred five million, five hundred seven thousand, six hundred fifty-eight".