18450389 has 4 divisors (see below), whose sum is σ = 19535724. Its totient is φ = 17365056.

The previous prime is 18450379. The next prime is 18450427. The reversal of 18450389 is 98305481.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14569489 + 3880900 = 3817^2 + 1970^2 .

It is a cyclic number.

It is not a de Polignac number, because 18450389 - 2⁴ = 18450373 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 (18450329) 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, 542642 + ... + 542675.

It is an arithmetic number, because the mean of its divisors is an integer number (4883931).

Almost surely, 2^18450389 is an apocalyptic number.

It is an amenable number.

18450389 is a deficient number, since it is larger than the sum of its proper divisors (1085335).

18450389 is a wasteful number, since it uses less digits than its factorization.

18450389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1085334.

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

The square root of 18450389 is about 4295.3916003084. The cubic root of 18450389 is about 264.2419966923.

The spelling of 18450389 in words is "eighteen million, four hundred fifty thousand, three hundred eighty-nine".