23201221 has 4 divisors (see below), whose sum is σ = 23694912. Its totient is φ = 22707532.

The previous prime is 23201197. The next prime is 23201251. The reversal of 23201221 is 12210232.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 23201221 - 2¹⁷ = 23070149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23201251) 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, 246775 + ... + 246868.

It is an arithmetic number, because the mean of its divisors is an integer number (5923728).

Almost surely, 2^23201221 is an apocalyptic number.

It is an amenable number.

23201221 is a deficient number, since it is larger than the sum of its proper divisors (493691).

23201221 is an equidigital number, since it uses as much as digits as its factorization.

23201221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 493690.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 23201221 is about 4816.7645780129. The cubic root of 23201221 is about 285.2136327852.

Adding to 23201221 its reverse (12210232), we get a palindrome (35411453).

The spelling of 23201221 in words is "twenty-three million, two hundred one thousand, two hundred twenty-one".