21105636024 has 96 divisors (see below), whose sum is σ = 58382190720. Its totient is φ = 6353160000.

The previous prime is 21105635963. The next prime is 21105636043. The reversal of 21105636024 is 42063650112.

It is a junction number, because it is equal to n+sod(n) for n = 21105635982 and 21105636000.

It is a congruent number.

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, 414439 + ... + 462569.

It is an arithmetic number, because the mean of its divisors is an integer number (608147820).

Almost surely, 2^21105636024 is an apocalyptic number.

21105636024 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 21105636024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29191095360).

21105636024 is an abundant number, since it is smaller than the sum of its proper divisors (37276554696).

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

21105636024 is a wasteful number, since it uses less digits than its factorization.

21105636024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48313 (or 48298 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The spelling of 21105636024 in words is "twenty-one billion, one hundred five million, six hundred thirty-six thousand, twenty-four".