23021530 has 48 divisors (see below), whose sum is σ = 49365504. Its totient is φ = 7564320.

The previous prime is 23021513. The next prime is 23021533. The reversal of 23021530 is 3512032.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23021533) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 223459 + ... + 223561.

It is an arithmetic number, because the mean of its divisors is an integer number (1028448).

Almost surely, 2^23021530 is an apocalyptic number.

23021530 is an abundant number, since it is smaller than the sum of its proper divisors (26343974).

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

23021530 is a wasteful number, since it uses less digits than its factorization.

23021530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 251 (or 148 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 16.

The square root of 23021530 is about 4798.0756559271. The cubic root of 23021530 is about 284.4754072039.

Adding to 23021530 its reverse (3512032), we get a palindrome (26533562).

The spelling of 23021530 in words is "twenty-three million, twenty-one thousand, five hundred thirty".