18213203 has 2 divisors, whose sum is σ = 18213204. Its totient is φ = 18213202.

The previous prime is 18213199. The next prime is 18213211. The reversal of 18213203 is 30231281.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18213203 - 2² = 18213199 is a prime.

It is not a weakly prime, because it can be changed into another prime (18213233) 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, 9106601 + 9106602.

It is an arithmetic number, because the mean of its divisors is an integer number (9106602).

Almost surely, 2^18213203 is an apocalyptic number.

18213203 is a deficient number, since it is larger than the sum of its proper divisors (1).

18213203 is an equidigital number, since it uses as much as digits as its factorization.

18213203 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 18213203 is about 4267.6929364705. The cubic root of 18213203 is about 263.1048028874.

Adding to 18213203 its reverse (30231281), we get a palindrome (48444484).

The spelling of 18213203 in words is "eighteen million, two hundred thirteen thousand, two hundred three".