23121221 has 8 divisors (see below), whose sum is σ = 23716800. Its totient is φ = 22533280.

The previous prime is 23121209. The next prime is 23121247. The reversal of 23121221 is 12212132.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 23121221 - 2²² = 18926917 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23121196 and 23121205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23121281) 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 7 ways as a sum of consecutive naturals, for example, 4490 + ... + 8148.

It is an arithmetic number, because the mean of its divisors is an integer number (2964600).

Almost surely, 2^23121221 is an apocalyptic number.

It is an amenable number.

23121221 is a deficient number, since it is larger than the sum of its proper divisors (595579).

23121221 is an equidigital number, since it uses as much as digits as its factorization.

23121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3819.

The product of its digits is 48, while the sum is 14.

The square root of 23121221 is about 4808.4530776540. The cubic root of 23121221 is about 284.8854407741.

Adding to 23121221 its reverse (12212132), we get a palindrome (35333353).

The spelling of 23121221 in words is "twenty-three million, one hundred twenty-one thousand, two hundred twenty-one".