18553109 has 4 divisors (see below), whose sum is σ = 18947904. Its totient is φ = 18158316.

The previous prime is 18553099. The next prime is 18553133. The reversal of 18553109 is 90135581.

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: 90135581 = 17 ⋅5302093.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18553109 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18553009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 197327 + ... + 197420.

It is an arithmetic number, because the mean of its divisors is an integer number (4736976).

Almost surely, 2^18553109 is an apocalyptic number.

It is an amenable number.

18553109 is a deficient number, since it is larger than the sum of its proper divisors (394795).

18553109 is an equidigital number, since it uses as much as digits as its factorization.

18553109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394794.

The product of its (nonzero) digits is 5400, while the sum is 32.

The square root of 18553109 is about 4307.3320048494. The cubic root of 18553109 is about 264.7314664374.

The spelling of 18553109 in words is "eighteen million, five hundred fifty-three thousand, one hundred nine".