18216003 has 48 divisors (see below), whose sum is σ = 29045760. Its totient is φ = 10108800.

The previous prime is 18215983. The next prime is 18216017. The reversal of 18216003 is 30061281.

It is not a de Polignac number, because 18216003 - 2¹⁴ = 18199619 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18216043) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 298593 + ... + 298653.

It is an arithmetic number, because the mean of its divisors is an integer number (605120).

Almost surely, 2^18216003 is an apocalyptic number.

18216003 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

18216003 is a deficient number, since it is larger than the sum of its proper divisors (10829757).

18216003 is a wasteful number, since it uses less digits than its factorization.

18216003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140 (or 127 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 18216003 is about 4268.0209699579. The cubic root of 18216003 is about 263.1182849696.

Adding to 18216003 its reverse (30061281), we get a palindrome (48277284).

The spelling of 18216003 in words is "eighteen million, two hundred sixteen thousand, three".