856217889792 has 220 divisors, whose sum is σ = 2585584778040. Its totient is φ = 282196721664.

The previous prime is 856217889773. The next prime is 856217889851. The reversal of 856217889792 is 297988712658.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a self number, because there is not a number n which added to its sum of digits gives 856217889792.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 7324023 + ... + 7440009.

It is an arithmetic number, because the mean of its divisors is an integer number (11752658082).

Almost surely, 2^856217889792 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 856217889792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1292792389020).

856217889792 is an abundant number, since it is smaller than the sum of its proper divisors (1729366888248).

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

856217889792 is a wasteful number, since it uses less digits than its factorization.

856217889792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116108 (or 116081 counting only the distinct ones).

The product of its digits is 243855360, while the sum is 72.

The spelling of 856217889792 in words is "eight hundred fifty-six billion, two hundred seventeen million, eight hundred eighty-nine thousand, seven hundred ninety-two".