18340389 has 6 divisors (see below), whose sum is σ = 26491686. Its totient is φ = 12226920.

The previous prime is 18340373. The next prime is 18340391. The reversal of 18340389 is 98304381.

It can be written as a sum of positive squares in only one way, i.e., 12723489 + 5616900 = 3567^2 + 2370^2 .

It is not a de Polignac number, because 18340389 - 2⁴ = 18340373 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18340349) 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 5 ways as a sum of consecutive naturals, for example, 1018902 + ... + 1018919.

It is an arithmetic number, because the mean of its divisors is an integer number (4415281).

Almost surely, 2^18340389 is an apocalyptic number.

It is an amenable number.

18340389 is a deficient number, since it is larger than the sum of its proper divisors (8151297).

18340389 is a wasteful number, since it uses less digits than its factorization.

18340389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2037827 (or 2037824 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 18340389 is about 4282.5680379884. The cubic root of 18340389 is about 263.7158185153.

The spelling of 18340389 in words is "eighteen million, three hundred forty thousand, three hundred eighty-nine".