21333259664640 has 2304 divisors, whose sum is σ = 95873476608000. Its totient is φ = 4363606425600.

The previous prime is 21333259664609. The next prime is 21333259664711. The reversal of 21333259664640 is 4646695233312.

21333259664640 is a `hidden beast` number, since 2 + 1 + 3 + 3 + 3 + 2 + 596 + 6 + 4 + 6 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (2304).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 68595690085 + ... + 68595690395.

It is an arithmetic number, because the mean of its divisors is an integer number (41611752000).

Almost surely, 2^{21333259664640} is an apocalyptic number.

21333259664640 is a gapful number since it is divisible by the number (20) 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 21333259664640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47936738304000).

21333259664640 is an abundant number, since it is smaller than the sum of its proper divisors (74540216943360).

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

21333259664640 is a wasteful number, since it uses less digits than its factorization.

21333259664640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681 (or 661 counting only the distinct ones).

The product of its (nonzero) digits is 16796160, while the sum is 54.

The spelling of 21333259664640 in words is "twenty-one trillion, three hundred thirty-three billion, two hundred fifty-nine million, six hundred sixty-four thousand, six hundred forty".