23218109 has 4 divisors (see below), whose sum is σ = 24227616. Its totient is φ = 22208604.

The previous prime is 23218051. The next prime is 23218121. The reversal of 23218109 is 90181232.

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 23218109 - 2²⁴ = 6440893 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23218159) 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, 504719 + ... + 504764.

It is an arithmetic number, because the mean of its divisors is an integer number (6056904).

Almost surely, 2^23218109 is an apocalyptic number.

It is an amenable number.

23218109 is a deficient number, since it is larger than the sum of its proper divisors (1009507).

23218109 is a wasteful number, since it uses less digits than its factorization.

23218109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1009506.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 23218109 is about 4818.5173030716. The cubic root of 23218109 is about 285.2828176444.

The spelling of 23218109 in words is "twenty-three million, two hundred eighteen thousand, one hundred nine".