21088336896 has 198 divisors, whose sum is σ = 66934541856. Its totient is φ = 6390067200.

The previous prime is 21088336891. The next prime is 21088336903. The reversal of 21088336896 is 69863388012.

It is a happy number.

21088336896 is a `hidden beast` number, since 210 + 8 + 8 + 336 + 8 + 96 = 666.

It is a tau number, because it is divible by the number of its divisors (198).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21088336891) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1105681 + ... + 1124591.

Almost surely, 2^21088336896 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 21088336896, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33467270928).

21088336896 is an abundant number, since it is smaller than the sum of its proper divisors (45846204960).

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

21088336896 is a wasteful number, since it uses less digits than its factorization.

21088336896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18959 (or 18927 counting only the distinct ones).

The product of its (nonzero) digits is 2985984, while the sum is 54.

The spelling of 21088336896 in words is "twenty-one billion, eighty-eight million, three hundred thirty-six thousand, eight hundred ninety-six".