21323020124 has 108 divisors (see below), whose sum is σ = 45214913016. Its totient is φ = 8772640128.

The previous prime is 21323020099. The next prime is 21323020133. The reversal of 21323020124 is 42102032312.

It is a junction number, because it is equal to n+sod(n) for n = 21323020096 and 21323020105.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 45659339 + ... + 45659805.

It is an arithmetic number, because the mean of its divisors is an integer number (418656602).

Almost surely, 2^21323020124 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 21323020124, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22607456508).

21323020124 is an abundant number, since it is smaller than the sum of its proper divisors (23891892892).

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

21323020124 is a wasteful number, since it uses less digits than its factorization.

21323020124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 820 (or 782 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21323020124 its reverse (42102032312), we get a palindrome (63425052436).

The spelling of 21323020124 in words is "twenty-one billion, three hundred twenty-three million, twenty thousand, one hundred twenty-four".