18018516 has 48 divisors (see below), whose sum is σ = 43944768. Its totient is φ = 5740800.

The previous prime is 18018503. The next prime is 18018529. The reversal of 18018516 is 61581081.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (18018503) and next prime (18018529).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25731 + ... + 26421.

It is an arithmetic number, because the mean of its divisors is an integer number (915516).

Almost surely, 2^18018516 is an apocalyptic number.

It is an amenable number.

18018516 is an abundant number, since it is smaller than the sum of its proper divisors (25926252).

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

18018516 is a wasteful number, since it uses less digits than its factorization.

18018516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 792 (or 790 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 30.

The square root of 18018516 is about 4244.8222577630. The cubic root of 18018516 is about 262.1639709362.

Adding to 18018516 its reverse (61581081), we get a palindrome (79599597).

The spelling of 18018516 in words is "eighteen million, eighteen thousand, five hundred sixteen".