18344609 has 4 divisors (see below), whose sum is σ = 18522816. Its totient is φ = 18166404.

The previous prime is 18344603. The next prime is 18344659. The reversal of 18344609 is 90644381.

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, and also an emirpimes, since its reverse is a distinct semiprime: 90644381 = 347 ⋅261223.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18344609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18344603) 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, 88949 + ... + 89154.

It is an arithmetic number, because the mean of its divisors is an integer number (4630704).

Almost surely, 2^18344609 is an apocalyptic number.

It is an amenable number.

18344609 is a deficient number, since it is larger than the sum of its proper divisors (178207).

18344609 is a wasteful number, since it uses less digits than its factorization.

18344609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178206.

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 18344609 is about 4283.0607046830. The cubic root of 18344609 is about 263.7360433755.

The spelling of 18344609 in words is "eighteen million, three hundred forty-four thousand, six hundred nine".