18318663 has 32 divisors (see below), whose sum is σ = 30424320. Its totient is φ = 10795680.

The previous prime is 18318659. The next prime is 18318667. The reversal of 18318663 is 36681381.

It is an interprime number because it is at equal distance from previous prime (18318659) and next prime (18318667).

It is not a de Polignac number, because 18318663 - 2² = 18318659 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18318667) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10156 + ... + 11822.

It is an arithmetic number, because the mean of its divisors is an integer number (950760).

Almost surely, 2^18318663 is an apocalyptic number.

18318663 is a deficient number, since it is larger than the sum of its proper divisors (12105657).

18318663 is a wasteful number, since it uses less digits than its factorization.

18318663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1724 (or 1718 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 18318663 is about 4280.0307241888. The cubic root of 18318663 is about 263.6116449025.

It can be divided in two parts, 18318 and 663, that added together give a palindrome (18981).

The spelling of 18318663 in words is "eighteen million, three hundred eighteen thousand, six hundred sixty-three".