23309221 has 4 divisors (see below), whose sum is σ = 25102252. Its totient is φ = 21516192.

The previous prime is 23309213. The next prime is 23309249. The reversal of 23309221 is 12290332.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8208225 + 15100996 = 2865^2 + 3886^2 .

It is a cyclic number.

It is not a de Polignac number, because 23309221 - 2³ = 23309213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23309192 and 23309201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23309291) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 896496 + ... + 896521.

It is an arithmetic number, because the mean of its divisors is an integer number (6275563).

Almost surely, 2^23309221 is an apocalyptic number.

It is an amenable number.

23309221 is a deficient number, since it is larger than the sum of its proper divisors (1793031).

23309221 is a wasteful number, since it uses less digits than its factorization.

23309221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1793030.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 23309221 is about 4827.9624066473. The cubic root of 23309221 is about 285.6554974641.

Adding to 23309221 its reverse (12290332), we get a palindrome (35599553).

The spelling of 23309221 in words is "twenty-three million, three hundred nine thousand, two hundred twenty-one".