21998801332956 has 576 divisors, whose sum is σ = 66174750351360. Its totient is φ = 5650686074880.

The previous prime is 21998801332931. The next prime is 21998801333011. The reversal of 21998801332956 is 65923310889912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 12549229776 + ... + 12549231528.

It is an arithmetic number, because the mean of its divisors is an integer number (114886719360).

Almost surely, 2^{21998801332956} 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 21998801332956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33087375175680).

21998801332956 is an abundant number, since it is smaller than the sum of its proper divisors (44175949018404).

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

21998801332956 is a wasteful number, since it uses less digits than its factorization.

21998801332956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2674 (or 2665 counting only the distinct ones).

The product of its (nonzero) digits is 50388480, while the sum is 66.

The spelling of 21998801332956 in words is "twenty-one trillion, nine hundred ninety-eight billion, eight hundred one million, three hundred thirty-two thousand, nine hundred fifty-six".