18211103 has 2 divisors, whose sum is σ = 18211104. Its totient is φ = 18211102.

The previous prime is 18211099. The next prime is 18211111. The reversal of 18211103 is 30111281.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18211103 - 2² = 18211099 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18211133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9105551 + 9105552.

It is an arithmetic number, because the mean of its divisors is an integer number (9105552).

Almost surely, 2^18211103 is an apocalyptic number.

18211103 is a deficient number, since it is larger than the sum of its proper divisors (1).

18211103 is an equidigital number, since it uses as much as digits as its factorization.

18211103 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 17.

The square root of 18211103 is about 4267.4468948072. The cubic root of 18211103 is about 263.0946904189.

Adding to 18211103 its reverse (30111281), we get a palindrome (48322384).

The spelling of 18211103 in words is "eighteen million, two hundred eleven thousand, one hundred three".