23940209 has 4 divisors (see below), whose sum is σ = 25200240. Its totient is φ = 22680180.

The previous prime is 23940197. The next prime is 23940223. The reversal of 23940209 is 90204932.

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 23940209 - 2⁸ = 23939953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23940509) 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, 629987 + ... + 630024.

It is an arithmetic number, because the mean of its divisors is an integer number (6300060).

Almost surely, 2^23940209 is an apocalyptic number.

It is an amenable number.

23940209 is a deficient number, since it is larger than the sum of its proper divisors (1260031).

23940209 is a wasteful number, since it uses less digits than its factorization.

23940209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1260030.

The product of its (nonzero) digits is 3888, while the sum is 29.

The square root of 23940209 is about 4892.8732867304. The cubic root of 23940209 is about 288.2101772440.

The spelling of 23940209 in words is "twenty-three million, nine hundred forty thousand, two hundred nine".