16856543880 has 960 divisors, whose sum is σ = 68594803200. Its totient is φ = 3695155200.

The previous prime is 16856543839. The next prime is 16856543917. The reversal of 16856543880 is 8834565861.

16856543880 is a `hidden beast` number, since 16 + 8 + 5 + 6 + 543 + 8 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 230911524 + ... + 230911596.

It is an arithmetic number, because the mean of its divisors is an integer number (71452920).

Almost surely, 2^16856543880 is an apocalyptic number.

16856543880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16856543880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34297401600).

16856543880 is an abundant number, since it is smaller than the sum of its proper divisors (51738259320).

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

16856543880 is a wasteful number, since it uses less digits than its factorization.

16856543880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168 (or 144 counting only the distinct ones).

The product of its (nonzero) digits is 5529600, while the sum is 54.

The spelling of 16856543880 in words is "sixteen billion, eight hundred fifty-six million, five hundred forty-three thousand, eight hundred eighty".