21669596928 has 324 divisors, whose sum is σ = 75381841080. Its totient is φ = 6190442496.

The previous prime is 21669596909. The next prime is 21669596929. The reversal of 21669596928 is 82969596612.

21669596928 is a `hidden beast` number, since 2 + 16 + 6 + 9 + 596 + 9 + 28 = 666.

It is a tau number, because it is divible by the number of its divisors (324).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21669596929) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 3044638 + ... + 3051746.

Almost surely, 2^21669596928 is an apocalyptic number.

21669596928 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 21669596928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37690920540).

21669596928 is an abundant number, since it is smaller than the sum of its proper divisors (53712244152).

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

21669596928 is an frugal number, since it uses more digits than its factorization.

21669596928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7154 (or 7121 counting only the distinct ones).

The product of its digits is 25194240, while the sum is 63.

The spelling of 21669596928 in words is "twenty-one billion, six hundred sixty-nine million, five hundred ninety-six thousand, nine hundred twenty-eight".