23221530 has 48 divisors (see below), whose sum is σ = 61293024. Its totient is φ = 6098400.

The previous prime is 23221487. The next prime is 23221531. The reversal of 23221530 is 3512232.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (23221531) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 4105 + ... + 7955.

It is an arithmetic number, because the mean of its divisors is an integer number (1276938).

Almost surely, 2^23221530 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 23221530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30646512).

23221530 is an abundant number, since it is smaller than the sum of its proper divisors (38071494).

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

23221530 is a wasteful number, since it uses less digits than its factorization.

23221530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3931 (or 3928 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 23221530 is about 4818.8722747132. The cubic root of 23221530 is about 285.2968283259.

Adding to 23221530 its reverse (3512232), we get a palindrome (26733762).

The spelling of 23221530 in words is "twenty-three million, two hundred twenty-one thousand, five hundred thirty".