21663205051024 has 160 divisors (see below), whose sum is σ = 48079722700800. Its totient is φ = 9393312614400.

The previous prime is 21663205051021. The next prime is 21663205051031. The reversal of 21663205051024 is 42015050236612.

It is not an unprimeable number, because it can be changed into a prime (21663205051021) 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, 26958249 + ... + 27750199.

It is an arithmetic number, because the mean of its divisors is an integer number (300498266880).

Almost surely, 2^{21663205051024} 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 21663205051024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24039861350400).

21663205051024 is an abundant number, since it is smaller than the sum of its proper divisors (26416517649776).

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

21663205051024 is a wasteful number, since it uses less digits than its factorization.

21663205051024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 792141 (or 792135 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 37.

Adding to 21663205051024 its reverse (42015050236612), we get a palindrome (63678255287636).

The spelling of 21663205051024 in words is "twenty-one trillion, six hundred sixty-three billion, two hundred five million, fifty-one thousand, twenty-four".