21543329120244 has 96 divisors (see below), whose sum is σ = 53811365287680. Its totient is φ = 6684364505088.

The previous prime is 21543329120213. The next prime is 21543329120249. The reversal of 21543329120244 is 44202192334512.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21543329120196 and 21543329120205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21543329120249) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15491592 + ... + 16824864.

It is an arithmetic number, because the mean of its divisors is an integer number (560535055080).

Almost surely, 2^{21543329120244} 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 21543329120244, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26905682643840).

21543329120244 is an abundant number, since it is smaller than the sum of its proper divisors (32268036167436).

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

21543329120244 is a wasteful number, since it uses less digits than its factorization.

21543329120244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1334169 (or 1334167 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 42.

The spelling of 21543329120244 in words is "twenty-one trillion, five hundred forty-three billion, three hundred twenty-nine million, one hundred twenty thousand, two hundred forty-four".