18304840 has 16 divisors (see below), whose sum is σ = 41185980. Its totient is φ = 7321920.

The previous prime is 18304837. The next prime is 18304861. The reversal of 18304840 is 4840381.

It can be written as a sum of positive squares in 2 ways, for example, as 16305444 + 1999396 = 4038^2 + 1414^2 .

It is a junction number, because it is equal to n+sod(n) for n = 18304799 and 18304808.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 228771 + ... + 228850.

Almost surely, 2^18304840 is an apocalyptic number.

18304840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18304840 is an abundant number, since it is smaller than the sum of its proper divisors (22881140).

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

18304840 is a wasteful number, since it uses less digits than its factorization.

18304840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 457632 (or 457628 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 28.

The square root of 18304840 is about 4278.4155945864. The cubic root of 18304840 is about 263.5453223640.

It can be divided in two parts, 1830 and 4840, that added together give a triangular number (6670 = T₁₁₅).

The spelling of 18304840 in words is "eighteen million, three hundred four thousand, eight hundred forty".