856408680 has 192 divisors, whose sum is σ = 2986200000. Its totient is φ = 218300544.

The previous prime is 856408669. The next prime is 856408687. The reversal of 856408680 is 86804658.

856408680 is a `hidden beast` number, since 8 + 564 + 0 + 8 + 6 + 80 = 666.

It is a super-5 number, since 5×856408680⁵ (a number of 46 digits) contains 55555 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856408687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 570571 + ... + 572069.

It is an arithmetic number, because the mean of its divisors is an integer number (15553125).

Almost surely, 2^856408680 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 856408680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1493100000).

856408680 is an abundant number, since it is smaller than the sum of its proper divisors (2129791320).

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

856408680 is a wasteful number, since it uses less digits than its factorization.

856408680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1565 (or 1532 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The square root of 856408680 is about 29264.4610406548. The cubic root of 856408680 is about 949.6429609368.

The spelling of 856408680 in words is "eight hundred fifty-six million, four hundred eight thousand, six hundred eighty".