18408379 has 4 divisors (see below), whose sum is σ = 20081880. Its totient is φ = 16734880.

The previous prime is 18408373. The next prime is 18408391. The reversal of 18408379 is 97380481.

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

It is a cyclic number.

It is not a de Polignac number, because 18408379 - 2³ = 18408371 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18408371) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 836734 + ... + 836755.

It is an arithmetic number, because the mean of its divisors is an integer number (5020470).

Almost surely, 2^18408379 is an apocalyptic number.

18408379 is a deficient number, since it is larger than the sum of its proper divisors (1673501).

18408379 is a wasteful number, since it uses less digits than its factorization.

18408379 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1673500.

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

The square root of 18408379 is about 4290.4986889638. The cubic root of 18408379 is about 264.0412919419.

The spelling of 18408379 in words is "eighteen million, four hundred eight thousand, three hundred seventy-nine".