856555819 has 6 divisors (see below), whose sum is σ = 996401724. Its totient is φ = 734190660.

The previous prime is 856555801. The next prime is 856555849. The reversal of 856555819 is 918555658.

It is not a de Polignac number, because 856555819 - 2⁵ = 856555787 is a prime.

It is a super-3 number, since 3×856555819³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (856555849) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8740317 + ... + 8740414.

It is an arithmetic number, because the mean of its divisors is an integer number (166066954).

Almost surely, 2^856555819 is an apocalyptic number.

856555819 is a deficient number, since it is larger than the sum of its proper divisors (139845905).

856555819 is a wasteful number, since it uses less digits than its factorization.

856555819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17480745 (or 17480738 counting only the distinct ones).

The product of its digits is 2160000, while the sum is 52.

The square root of 856555819 is about 29266.9748863800. The cubic root of 856555819 is about 949.6973436622.

The spelling of 856555819 in words is "eight hundred fifty-six million, five hundred fifty-five thousand, eight hundred nineteen".