21273738831072 has 1296 divisors, whose sum is σ = 79524279119376. Its totient is φ = 5345657856000.

The previous prime is 21273738831019. The next prime is 21273738831077. The reversal of 21273738831072 is 27013883737212.

21273738831072 is a `hidden beast` number, since 2 + 127 + 37 + 388 + 3 + 107 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21273738831077) by changing a digit.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 11812180572 + ... + 11812182372.

It is an arithmetic number, because the mean of its divisors is an integer number (61361326481).

Almost surely, 2^{21273738831072} 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 21273738831072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39762139559688).

21273738831072 is an abundant number, since it is smaller than the sum of its proper divisors (58250540288304).

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

21273738831072 is a wasteful number, since it uses less digits than its factorization.

21273738831072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1973 (or 1924 counting only the distinct ones).

The product of its (nonzero) digits is 4741632, while the sum is 54.

The spelling of 21273738831072 in words is "twenty-one trillion, two hundred seventy-three billion, seven hundred thirty-eight million, eight hundred thirty-one thousand, seventy-two".