21669964728696 has 256 divisors, whose sum is σ = 61611580800000. Its totient is φ = 7054568142336.

The previous prime is 21669964728679. The next prime is 21669964728739. The reversal of 21669964728696 is 69682746996612.

21669964728696 is a `hidden beast` number, since 2 + 1 + 6 + 69 + 9 + 6 + 472 + 86 + 9 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2948692030 + ... + 2948699378.

It is an arithmetic number, because the mean of its divisors is an integer number (240670237500).

Almost surely, 2^{21669964728696} 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 21669964728696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30805790400000).

21669964728696 is an abundant number, since it is smaller than the sum of its proper divisors (39941616071304).

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

21669964728696 is a wasteful number, since it uses less digits than its factorization.

21669964728696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8563 (or 8553 counting only the distinct ones).

The product of its digits is 5079158784, while the sum is 81.

The spelling of 21669964728696 in words is "twenty-one trillion, six hundred sixty-nine billion, nine hundred sixty-four million, seven hundred twenty-eight thousand, six hundred ninety-six".