16856328820 has 24 divisors (see below), whose sum is σ = 36066185064. Its totient is φ = 6615313536.

The previous prime is 16856328809. The next prime is 16856328877. The reversal of 16856328820 is 2882365861.

It can be written as a sum of positive squares in 4 ways, for example, as 3335755536 + 13520573284 = 57756^2 + 116278^2 .

It is a hoax number, since the sum of its digits (49) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7950039 + ... + 7952158.

It is an arithmetic number, because the mean of its divisors is an integer number (1502757711).

Almost surely, 2^16856328820 is an apocalyptic number.

16856328820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16856328820 is an abundant number, since it is smaller than the sum of its proper divisors (19209856244).

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

16856328820 is a wasteful number, since it uses less digits than its factorization.

16856328820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15902259 (or 15902257 counting only the distinct ones).

The product of its (nonzero) digits is 1105920, while the sum is 49.

The spelling of 16856328820 in words is "sixteen billion, eight hundred fifty-six million, three hundred twenty-eight thousand, eight hundred twenty".