18209423 has 4 divisors (see below), whose sum is σ = 18228480. Its totient is φ = 18190368.

The previous prime is 18209407. The next prime is 18209437. The reversal of 18209423 is 32490281.

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 18209423 - 2⁴ = 18209407 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 (18209483) 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, 8015 + ... + 10032.

It is an arithmetic number, because the mean of its divisors is an integer number (4557120).

Almost surely, 2^18209423 is an apocalyptic number.

18209423 is a deficient number, since it is larger than the sum of its proper divisors (19057).

18209423 is a wasteful number, since it uses less digits than its factorization.

18209423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19056.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 18209423 is about 4267.2500512625. The cubic root of 18209423 is about 263.0865998844.

The spelling of 18209423 in words is "eighteen million, two hundred nine thousand, four hundred twenty-three".