23306721 has 4 divisors (see below), whose sum is σ = 31075632. Its totient is φ = 15537812.

The previous prime is 23306719. The next prime is 23306743. The reversal of 23306721 is 12760332.

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 23306721 - 2¹ = 23306719 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 23306691 and 23306700.

It is not an unprimeable number, because it can be changed into a prime (23306021) 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, 3884451 + ... + 3884456.

It is an arithmetic number, because the mean of its divisors is an integer number (7768908).

Almost surely, 2^23306721 is an apocalyptic number.

It is an amenable number.

23306721 is a deficient number, since it is larger than the sum of its proper divisors (7768911).

23306721 is an equidigital number, since it uses as much as digits as its factorization.

23306721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7768910.

The product of its (nonzero) digits is 1512, while the sum is 24.

The square root of 23306721 is about 4827.7034913093. The cubic root of 23306721 is about 285.6452845635.

The spelling of 23306721 in words is "twenty-three million, three hundred six thousand, seven hundred twenty-one".