18068021 has 4 divisors (see below), whose sum is σ = 18285792. Its totient is φ = 17850252.

The previous prime is 18067999. The next prime is 18068023. The reversal of 18068021 is 12086081.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18068021 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 (18068023) 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, 108761 + ... + 108926.

It is an arithmetic number, because the mean of its divisors is an integer number (4571448).

Almost surely, 2^18068021 is an apocalyptic number.

It is an amenable number.

18068021 is a deficient number, since it is larger than the sum of its proper divisors (217771).

18068021 is an equidigital number, since it uses as much as digits as its factorization.

18068021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217770.

The product of its (nonzero) digits is 768, while the sum is 26.

The square root of 18068021 is about 4250.6494797854. The cubic root of 18068021 is about 262.4038456595.

The spelling of 18068021 in words is "eighteen million, sixty-eight thousand, twenty-one".