18208385 has 8 divisors (see below), whose sum is σ = 23530920. Its totient is φ = 13446144.

The previous prime is 18208373. The next prime is 18208391. The reversal of 18208385 is 58380281.

It can be written as a sum of positive squares in 4 ways, for example, as 128881 + 18079504 = 359^2 + 4252^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18208385 - 2¹² = 18204289 is a prime.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 140000 + ... + 140129.

It is an arithmetic number, because the mean of its divisors is an integer number (2941365).

Almost surely, 2^18208385 is an apocalyptic number.

It is an amenable number.

18208385 is a deficient number, since it is larger than the sum of its proper divisors (5322535).

18208385 is a wasteful number, since it uses less digits than its factorization.

18208385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280147.

The product of its (nonzero) digits is 15360, while the sum is 35.

The square root of 18208385 is about 4267.1284255340. The cubic root of 18208385 is about 263.0816008411.

The spelling of 18208385 in words is "eighteen million, two hundred eight thousand, three hundred eighty-five".