16691287680 has 320 divisors, whose sum is σ = 62203680000. Its totient is φ = 4257183744.

The previous prime is 16691287673. The next prime is 16691287709. The reversal of 16691287680 is 8678219661.

It is a tau number, because it is divible by the number of its divisors (320).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1185321 + ... + 1199319.

It is an arithmetic number, because the mean of its divisors is an integer number (194386500).

Almost surely, 2^16691287680 is an apocalyptic number.

16691287680 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 16691287680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31101840000).

16691287680 is an abundant number, since it is smaller than the sum of its proper divisors (45512392320).

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

16691287680 is a wasteful number, since it uses less digits than its factorization.

16691287680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14053 (or 14032 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The spelling of 16691287680 in words is "sixteen billion, six hundred ninety-one million, two hundred eighty-seven thousand, six hundred eighty".