18020111 has 2 divisors, whose sum is σ = 18020112. Its totient is φ = 18020110.

The previous prime is 18020089. The next prime is 18020143. The reversal of 18020111 is 11102081.

It is a weak prime.

It is an emirp because it is prime and its reverse (11102081) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18020111 - 2²² = 13825807 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18020011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9010055 + 9010056.

It is an arithmetic number, because the mean of its divisors is an integer number (9010056).

Almost surely, 2^18020111 is an apocalyptic number.

18020111 is a deficient number, since it is larger than the sum of its proper divisors (1).

18020111 is an equidigital number, since it uses as much as digits as its factorization.

18020111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 14.

The square root of 18020111 is about 4245.0101295521. The cubic root of 18020111 is about 262.1717062975.

Adding to 18020111 its reverse (11102081), we get a palindrome (29122192).

The spelling of 18020111 in words is "eighteen million, twenty thousand, one hundred eleven".