18342809 has 4 divisors (see below), whose sum is σ = 19308240. Its totient is φ = 17377380.

The previous prime is 18342803. The next prime is 18342817. The reversal of 18342809 is 90824381.

It is a happy number.

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 18342809 - 2¹² = 18338713 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18342803) 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, 482687 + ... + 482724.

It is an arithmetic number, because the mean of its divisors is an integer number (4827060).

Almost surely, 2^18342809 is an apocalyptic number.

18342809 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

18342809 is a deficient number, since it is larger than the sum of its proper divisors (965431).

18342809 is an equidigital number, since it uses as much as digits as its factorization.

18342809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 965430.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 18342809 is about 4282.8505694222. The cubic root of 18342809 is about 263.7274170373.

The spelling of 18342809 in words is "eighteen million, three hundred forty-two thousand, eight hundred nine".