21399509200896 has 936 divisors, whose sum is σ = 68246655020544. Its totient is φ = 6689440235520.

The previous prime is 21399509200831. The next prime is 21399509200963. The reversal of 21399509200896 is 69800290599312.

21399509200896 is a `hidden beast` number, since 2 + 1 + 39 + 9 + 509 + 2 + 0 + 0 + 8 + 96 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 168500072385 + ... + 168500072511.

Almost surely, 2^{21399509200896} 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 21399509200896, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34123327510272).

21399509200896 is an abundant number, since it is smaller than the sum of its proper divisors (46847145819648).

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

21399509200896 is an frugal number, since it uses more digits than its factorization.

21399509200896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 367 (or 206 counting only the distinct ones).

The product of its (nonzero) digits is 18895680, while the sum is 63.

The spelling of 21399509200896 in words is "twenty-one trillion, three hundred ninety-nine billion, five hundred nine million, two hundred thousand, eight hundred ninety-six".