16681856720 has 20 divisors (see below), whose sum is σ = 38785317060. Its totient is φ = 6672742656.

The previous prime is 16681856701. The next prime is 16681856753. The reversal of 16681856720 is 2765818661.

16681856720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 10885166224 + 5796690496 = 104332^2 + 76136^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104261525 + ... + 104261684.

It is an arithmetic number, because the mean of its divisors is an integer number (1939265853).

Almost surely, 2^16681856720 is an apocalyptic number.

16681856720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16681856720 is an abundant number, since it is smaller than the sum of its proper divisors (22103460340).

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

16681856720 is a wasteful number, since it uses less digits than its factorization.

16681856720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208523222 (or 208523216 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 50.

The spelling of 16681856720 in words is "sixteen billion, six hundred eighty-one million, eight hundred fifty-six thousand, seven hundred twenty".