21973282539264 has 864 divisors, whose sum is σ = 76550789145600. Its totient is φ = 6198454886400.

The previous prime is 21973282539251. The next prime is 21973282539343. The reversal of 21973282539264 is 46293528237912.

21973282539264 is a `hidden beast` number, since 2 + 1 + 9 + 7 + 32 + 8 + 2 + 539 + 2 + 64 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 16659045997 + ... + 16659047315.

It is an arithmetic number, because the mean of its divisors is an integer number (88600450400).

Almost surely, 2^{21973282539264} is an apocalyptic number.

21973282539264 is a gapful number since it is divisible by the number (24) 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 21973282539264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38275394572800).

21973282539264 is an abundant number, since it is smaller than the sum of its proper divisors (54577506606336).

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

21973282539264 is a wasteful number, since it uses less digits than its factorization.

21973282539264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1946 (or 1919 counting only the distinct ones).

The product of its digits is 78382080, while the sum is 63.

The spelling of 21973282539264 in words is "twenty-one trillion, nine hundred seventy-three billion, two hundred eighty-two million, five hundred thirty-nine thousand, two hundred sixty-four".