21968879616 has 384 divisors, whose sum is σ = 68701651200. Its totient is φ = 7007109120.

The previous prime is 21968879593. The next prime is 21968879623. The reversal of 21968879616 is 61697886912.

21968879616 is a `hidden beast` number, since 2 + 1 + 9 + 6 + 8 + 8 + 7 + 9 + 616 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 246841300 + ... + 246841388.

It is an arithmetic number, because the mean of its divisors is an integer number (178910550).

Almost surely, 2^21968879616 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21968879616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34350825600).

21968879616 is an abundant number, since it is smaller than the sum of its proper divisors (46732771584).

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

21968879616 is an frugal number, since it uses more digits than its factorization.

21968879616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165 (or 125 counting only the distinct ones).

The product of its digits is 15676416, while the sum is 63.

The spelling of 21968879616 in words is "twenty-one billion, nine hundred sixty-eight million, eight hundred seventy-nine thousand, six hundred sixteen".