23238991 has 4 divisors (see below), whose sum is σ = 23261800. Its totient is φ = 23216184.

The previous prime is 23238977. The next prime is 23239001. The reversal of 23238991 is 19983232.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 23238991 - 2⁵ = 23238959 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 23238991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23238931) 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 3 ways as a sum of consecutive naturals, for example, 9801 + ... + 11938.

It is an arithmetic number, because the mean of its divisors is an integer number (5815450).

Almost surely, 2^23238991 is an apocalyptic number.

23238991 is a deficient number, since it is larger than the sum of its proper divisors (22809).

23238991 is a wasteful number, since it uses less digits than its factorization.

23238991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22808.

The product of its digits is 23328, while the sum is 37.

The square root of 23238991 is about 4820.6836652077. The cubic root of 23238991 is about 285.3683183015.

The spelling of 23238991 in words is "twenty-three million, two hundred thirty-eight thousand, nine hundred ninety-one".