18045503 has 16 divisors (see below), whose sum is σ = 21479424. Its totient is φ = 14834880.

The previous prime is 18045491. The next prime is 18045541. The reversal of 18045503 is 30554081.

It is a Cunningham number, because it is equal to 4248²-1.

It is a cyclic number.

It is not a de Polignac number, because 18045503 - 2⁶ = 18045439 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18045553) 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, 29426 + ... + 30032.

It is an arithmetic number, because the mean of its divisors is an integer number (1342464).

Almost surely, 2^18045503 is an apocalyptic number.

18045503 is a deficient number, since it is larger than the sum of its proper divisors (3433921).

18045503 is a wasteful number, since it uses less digits than its factorization.

18045503 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 782.

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 18045503 is about 4247.9998822976. Note that the first 3 decimals coincide. The cubic root of 18045503 is about 262.2947898828.

Adding to 18045503 its reverse (30554081), we get a palindrome (48599584).

The spelling of 18045503 in words is "eighteen million, forty-five thousand, five hundred three".