856661676 has 72 divisors (see below), whose sum is σ = 2172248064. Its totient is φ = 262641600.

The previous prime is 856661669. The next prime is 856661677. The reversal of 856661676 is 676166658.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (856661677) 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 23 ways as a sum of consecutive naturals, for example, 743701 + ... + 744851.

It is an arithmetic number, because the mean of its divisors is an integer number (30170112).

Almost surely, 2^856661676 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 856661676, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1086124032).

856661676 is an abundant number, since it is smaller than the sum of its proper divisors (1315586388).

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

856661676 is a wasteful number, since it uses less digits than its factorization.

856661676 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1551 (or 1536 counting only the distinct ones).

The product of its digits is 2177280, while the sum is 51.

The square root of 856661676 is about 29268.7833023513. The cubic root of 856661676 is about 949.7364646660.

The spelling of 856661676 in words is "eight hundred fifty-six million, six hundred sixty-one thousand, six hundred seventy-six".