856855267128 has 640 divisors, whose sum is σ = 2904765726720. Its totient is φ = 230854821120.

The previous prime is 856855267069. The next prime is 856855267129. The reversal of 856855267128 is 821762558658.

It is a happy number.

856855267128 is a `hidden beast` number, since 8 + 5 + 6 + 8 + 552 + 6 + 71 + 2 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856855267129) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 970390575 + ... + 970391457.

It is an arithmetic number, because the mean of its divisors is an integer number (4538696448).

Almost surely, 2^856855267128 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 856855267128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1452382863360).

856855267128 is an abundant number, since it is smaller than the sum of its proper divisors (2047910459592).

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

856855267128 is a wasteful number, since it uses less digits than its factorization.

856855267128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1109 (or 1096 counting only the distinct ones).

The product of its digits is 64512000, while the sum is 63.

The spelling of 856855267128 in words is "eight hundred fifty-six billion, eight hundred fifty-five million, two hundred sixty-seven thousand, one hundred twenty-eight".