18130728 has 64 divisors (see below), whose sum is σ = 56517120. Its totient is φ = 4708800.

The previous prime is 18130727. The next prime is 18130729. The reversal of 18130728 is 82703181.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (18130727) and next prime (18130729).

It is a junction number, because it is equal to n+sod(n) for n = 18130695 and 18130704.

It is not an unprimeable number, because it can be changed into a prime (18130727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3058 + ... + 6753.

It is an arithmetic number, because the mean of its divisors is an integer number (883080).

Almost surely, 2^18130728 is an apocalyptic number.

It is an amenable number.

18130728 is an abundant number, since it is smaller than the sum of its proper divisors (38386392).

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

18130728 is a wasteful number, since it uses less digits than its factorization.

18130728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9838 (or 9834 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 30.

The square root of 18130728 is about 4258.0192578240. The cubic root of 18130728 is about 262.7070620218.

The spelling of 18130728 in words is "eighteen million, one hundred thirty thousand, seven hundred twenty-eight".