18354809 has 4 divisors (see below), whose sum is σ = 20023440. Its totient is φ = 16686180.

The previous prime is 18354799. The next prime is 18354823. The reversal of 18354809 is 90845381.

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 a de Polignac number, because none of the positive numbers 2^k-18354809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18354829) 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, 834299 + ... + 834320.

It is an arithmetic number, because the mean of its divisors is an integer number (5005860).

Almost surely, 2^18354809 is an apocalyptic number.

It is an amenable number.

18354809 is a deficient number, since it is larger than the sum of its proper divisors (1668631).

18354809 is a wasteful number, since it uses less digits than its factorization.

18354809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1668630.

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 18354809 is about 4284.2512764776. The cubic root of 18354809 is about 263.7849153031.

The spelling of 18354809 in words is "eighteen million, three hundred fifty-four thousand, eight hundred nine".