18408863 has 8 divisors (see below), whose sum is σ = 20217216. Its totient is φ = 16623000.

The previous prime is 18408847. The next prime is 18408883. The reversal of 18408863 is 36880481.

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 18408863 - 2⁴ = 18408847 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 (18408833) 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, 3881 + ... + 7202.

It is an arithmetic number, because the mean of its divisors is an integer number (2527152).

Almost surely, 2^18408863 is an apocalyptic number.

18408863 is a deficient number, since it is larger than the sum of its proper divisors (1808353).

18408863 is a wasteful number, since it uses less digits than its factorization.

18408863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11245.

The product of its (nonzero) digits is 36864, while the sum is 38.

The square root of 18408863 is about 4290.5550922928. Note that the first 3 decimals coincide. The cubic root of 18408863 is about 264.0436060125.

The spelling of 18408863 in words is "eighteen million, four hundred eight thousand, eight hundred sixty-three".