23920991 has 4 divisors (see below), whose sum is σ = 24073512. Its totient is φ = 23768472.

The previous prime is 23920973. The next prime is 23921011. The reversal of 23920991 is 19902932.

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 23920991 - 2¹⁰ = 23919967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23920961) 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, 76025 + ... + 76338.

It is an arithmetic number, because the mean of its divisors is an integer number (6018378).

Almost surely, 2^23920991 is an apocalyptic number.

23920991 is a deficient number, since it is larger than the sum of its proper divisors (152521).

23920991 is a wasteful number, since it uses less digits than its factorization.

23920991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152520.

The product of its (nonzero) digits is 8748, while the sum is 35.

The square root of 23920991 is about 4890.9090157148. The cubic root of 23920991 is about 288.1330363699.

The spelling of 23920991 in words is "twenty-three million, nine hundred twenty thousand, nine hundred ninety-one".