18640308 has 24 divisors (see below), whose sum is σ = 43896160. Its totient is φ = 6156000.

The previous prime is 18640289. The next prime is 18640309. The reversal of 18640308 is 80304681.

It is a happy number.

It is a super-2 number, since 2×18640308² = 694922164669728, which contains 22 as substring.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18640309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5818 + ... + 8433.

Almost surely, 2^18640308 is an apocalyptic number.

It is an amenable number.

18640308 is an abundant number, since it is smaller than the sum of its proper divisors (25255852).

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

18640308 is a wasteful number, since it uses less digits than its factorization.

18640308 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14367 (or 14365 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 18640308 is about 4317.4422983984. The cubic root of 18640308 is about 265.1455614209.

Adding to 18640308 its reverse (80304681), we get a palindrome (98944989).

The spelling of 18640308 in words is "eighteen million, six hundred forty thousand, three hundred eight".