23221012520 has 128 divisors (see below), whose sum is σ = 56576931840. Its totient is φ = 8552248320.

The previous prime is 23221012513. The next prime is 23221012531. The reversal of 23221012520 is 2521012232.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 23221012492 and 23221012501.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5616374 + ... + 5620506.

It is an arithmetic number, because the mean of its divisors is an integer number (442007280).

Almost surely, 2^23221012520 is an apocalyptic number.

23221012520 is a gapful number since it is divisible by the number (20) 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 23221012520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28288465920).

23221012520 is an abundant number, since it is smaller than the sum of its proper divisors (33355919320).

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

23221012520 is a wasteful number, since it uses less digits than its factorization.

23221012520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4395 (or 4391 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

Adding to 23221012520 its reverse (2521012232), we get a palindrome (25742024752).

The spelling of 23221012520 in words is "twenty-three billion, two hundred twenty-one million, twelve thousand, five hundred twenty".