18021163 has 4 divisors (see below), whose sum is σ = 18404640. Its totient is φ = 17637688.

The previous prime is 18021131. The next prime is 18021187. The reversal of 18021163 is 36112081.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18021163 - 2⁵ = 18021131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18021193) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 191668 + ... + 191761.

It is an arithmetic number, because the mean of its divisors is an integer number (4601160).

Almost surely, 2^18021163 is an apocalyptic number.

18021163 is a deficient number, since it is larger than the sum of its proper divisors (383477).

18021163 is an equidigital number, since it uses as much as digits as its factorization.

18021163 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383476.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 18021163 is about 4245.1340379310. The cubic root of 18021163 is about 262.1768079914.

The spelling of 18021163 in words is "eighteen million, twenty-one thousand, one hundred sixty-three".