18830393 has 4 divisors (see below), whose sum is σ = 18890868. Its totient is φ = 18769920.

The previous prime is 18830389. The next prime is 18830401. The reversal of 18830393 is 39303881.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 39303881 = 17 ⋅2311993.

It can be written as a sum of positive squares in 2 ways, for example, as 8248384 + 10582009 = 2872^2 + 3253^2 .

It is a cyclic number.

It is not a de Polignac number, because 18830393 - 2² = 18830389 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18830363) 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, 29768 + ... + 30393.

It is an arithmetic number, because the mean of its divisors is an integer number (4722717).

Almost surely, 2^18830393 is an apocalyptic number.

It is an amenable number.

18830393 is a deficient number, since it is larger than the sum of its proper divisors (60475).

18830393 is an equidigital number, since it uses as much as digits as its factorization.

18830393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60474.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 18830393 is about 4339.4000737429. The cubic root of 18830393 is about 266.0437911961.

The spelling of 18830393 in words is "eighteen million, eight hundred thirty thousand, three hundred ninety-three".