23291221 has 8 divisors (see below), whose sum is σ = 23946840. Its totient is φ = 22643712.

The previous prime is 23291209. The next prime is 23291227. The reversal of 23291221 is 12219232.

It can be written as a sum of positive squares in 4 ways, for example, as 2002225 + 21288996 = 1415^2 + 4614^2 .

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 23291221 - 2⁵ = 23291189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23291192 and 23291201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23291227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4045 + ... + 7933.

It is an arithmetic number, because the mean of its divisors is an integer number (2993355).

Almost surely, 2^23291221 is an apocalyptic number.

It is an amenable number.

23291221 is a deficient number, since it is larger than the sum of its proper divisors (655619).

23291221 is a wasteful number, since it uses less digits than its factorization.

23291221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4055.

The product of its digits is 432, while the sum is 22.

The square root of 23291221 is about 4826.0979061764. The cubic root of 23291221 is about 285.5819482728.

The spelling of 23291221 in words is "twenty-three million, two hundred ninety-one thousand, two hundred twenty-one".