18003604 has 6 divisors (see below), whose sum is σ = 31506314. Its totient is φ = 9001800.

The previous prime is 18003599. The next prime is 18003607. The reversal of 18003604 is 40630081.

It can be written as a sum of positive squares in only one way, i.e., 16793604 + 1210000 = 4098^2 + 1100^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18003607) by changing a digit.

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 as a sum of consecutive naturals, namely, 2250447 + ... + 2250454.

Almost surely, 2^18003604 is an apocalyptic number.

It is an amenable number.

18003604 is a deficient number, since it is larger than the sum of its proper divisors (13502710).

18003604 is a wasteful number, since it uses less digits than its factorization.

18003604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4500905 (or 4500903 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 18003604 is about 4243.0654013343. The cubic root of 18003604 is about 262.0916292758.

Adding to 18003604 its reverse (40630081), we get a palindrome (58633685).

The spelling of 18003604 in words is "eighteen million, three thousand, six hundred four".