21109569159168 has 1904 divisors, whose sum is σ = 79217383034880. Its totient is φ = 5485419823104.

The previous prime is 21109569159157. The next prime is 21109569159221. The reversal of 21109569159168 is 86195196590112.

21109569159168 is a `hidden beast` number, since 2 + 1 + 1 + 0 + 9 + 569 + 1 + 5 + 9 + 1 + 68 = 666.

It is a tau number, because it is divible by the number of its divisors (1904).

It is a super-2 number, since 2×21109569159168² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

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 111 ways as a sum of consecutive naturals, for example, 267209736153 + ... + 267209736231.

Almost surely, 2^{21109569159168} is an apocalyptic number.

21109569159168 is a gapful number since it is divisible by the number (28) 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 21109569159168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39608691517440).

21109569159168 is an abundant number, since it is smaller than the sum of its proper divisors (58107813875712).

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

21109569159168 is an frugal number, since it uses more digits than its factorization.

21109569159168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 10497600, while the sum is 63.

The spelling of 21109569159168 in words is "twenty-one trillion, one hundred nine billion, five hundred sixty-nine million, one hundred fifty-nine thousand, one hundred sixty-eight".