23159921 has 2 divisors, whose sum is σ = 23159922. Its totient is φ = 23159920.

The previous prime is 23159909. The next prime is 23159923. The reversal of 23159921 is 12995132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18490000 + 4669921 = 4300^2 + 2161^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23159921 is a prime.

It is a Sophie Germain prime.

Together with 23159923, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (23159923) 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 as a sum of consecutive naturals, namely, 11579960 + 11579961.

It is an arithmetic number, because the mean of its divisors is an integer number (11579961).

Almost surely, 2^23159921 is an apocalyptic number.

It is an amenable number.

23159921 is a deficient number, since it is larger than the sum of its proper divisors (1).

23159921 is an equidigital number, since it uses as much as digits as its factorization.

23159921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4860, while the sum is 32.

The square root of 23159921 is about 4812.4755583795. The cubic root of 23159921 is about 285.0442980287.

The spelling of 23159921 in words is "twenty-three million, one hundred fifty-nine thousand, nine hundred twenty-one".