21365311104 has 192 divisors, whose sum is σ = 64275993600. Its totient is φ = 6803896320.

The previous prime is 21365311067. The next prime is 21365311127. The reversal of 21365311104 is 40111356312.

It is a happy number.

21365311104 is a `hidden beast` number, since 2 + 1 + 3 + 653 + 1 + 1 + 1 + 0 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2817462 + ... + 2825034.

It is an arithmetic number, because the mean of its divisors is an integer number (334770800).

Almost surely, 2^21365311104 is an apocalyptic number.

21365311104 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 21365311104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32137996800).

21365311104 is an abundant number, since it is smaller than the sum of its proper divisors (42910682496).

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

21365311104 is a wasteful number, since it uses less digits than its factorization.

21365311104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7703 (or 7688 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

Adding to 21365311104 its reverse (40111356312), we get a palindrome (61476667416).

The spelling of 21365311104 in words is "twenty-one billion, three hundred sixty-five million, three hundred eleven thousand, one hundred four".