18303021 has 12 divisors (see below), whose sum is σ = 28841280. Its totient is φ = 11092680.

The previous prime is 18303001. The next prime is 18303037. The reversal of 18303021 is 12030381.

It is not a de Polignac number, because 18303021 - 2¹⁷ = 18171949 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 18302985 and 18303003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18303001) 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 in 11 ways as a sum of consecutive naturals, for example, 92341 + ... + 92538.

It is an arithmetic number, because the mean of its divisors is an integer number (2403440).

Almost surely, 2^18303021 is an apocalyptic number.

18303021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18303021 is a deficient number, since it is larger than the sum of its proper divisors (10538259).

18303021 is a wasteful number, since it uses less digits than its factorization.

18303021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184896 (or 184893 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 18303021 is about 4278.2030106109. The cubic root of 18303021 is about 263.5365923447.

It can be divided in two parts, 1830 and 3021, that added together give a triangular number (4851 = T₉₈).

The spelling of 18303021 in words is "eighteen million, three hundred three thousand, twenty-one".