18078493 has 8 divisors (see below), whose sum is σ = 18314208. Its totient is φ = 17844624.

The previous prime is 18078491. The next prime is 18078521. The reversal of 18078493 is 39487081.

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 18078493 - 2¹ = 18078491 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 (18078491) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31830 + ... + 32392.

It is an arithmetic number, because the mean of its divisors is an integer number (2289276).

Almost surely, 2^18078493 is an apocalyptic number.

It is an amenable number.

18078493 is a deficient number, since it is larger than the sum of its proper divisors (235715).

18078493 is a wasteful number, since it uses less digits than its factorization.

18078493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 923.

The product of its (nonzero) digits is 48384, while the sum is 40.

The square root of 18078493 is about 4251.8811131075. The cubic root of 18078493 is about 262.4545312025.

The spelling of 18078493 in words is "eighteen million, seventy-eight thousand, four hundred ninety-three".