18321612 has 24 divisors (see below), whose sum is σ = 43745856. Its totient is φ = 5965008.

The previous prime is 18321607. The next prime is 18321659. The reversal of 18321612 is 21612381.

It is an alternating number because its digits alternate between odd and even.

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 7 ways as a sum of consecutive naturals, for example, 17238 + ... + 18269.

It is an arithmetic number, because the mean of its divisors is an integer number (1822744).

Almost surely, 2^18321612 is an apocalyptic number.

18321612 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18321612 is an abundant number, since it is smaller than the sum of its proper divisors (25424244).

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

18321612 is a wasteful number, since it uses less digits than its factorization.

18321612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35557 (or 35555 counting only the distinct ones).

The product of its digits is 576, while the sum is 24.

The square root of 18321612 is about 4280.3752171977. The cubic root of 18321612 is about 263.6257898400.

Adding to 18321612 its reverse (21612381), we get a palindrome (39933993).

The spelling of 18321612 in words is "eighteen million, three hundred twenty-one thousand, six hundred twelve".