30918 has 8 divisors (see below), whose sum is σ = 61848. Its totient is φ = 10304.

The previous prime is 30911. The next prime is 30931. The reversal of 30918 is 81903.

30918 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

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

30918 is an admirable number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 30894 and 30903.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 30918.

It is not an unprimeable number, because it can be changed into a prime (30911) 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, 2571 + ... + 2582.

It is an arithmetic number, because the mean of its divisors is an integer number (7731).

2³⁰⁹¹⁸ is an apocalyptic number.

30918 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30924).

30918 is a wasteful number, since it uses less digits than its factorization.

30918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5158.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 30918 is about 175.8351500696. The cubic root of 30918 is about 31.3860838709.

The spelling of 30918 in words is "thirty thousand, nine hundred eighteen".