218261903 has 2 divisors, whose sum is σ = 218261904. Its totient is φ = 218261902.

The previous prime is 218261867. The next prime is 218261933. The reversal of 218261903 is 309162812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 218261903 - 2⁶ = 218261839 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 218261903.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218261933) 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, 109130951 + 109130952.

It is an arithmetic number, because the mean of its divisors is an integer number (109130952).

Almost surely, 2^218261903 is an apocalyptic number.

218261903 is a deficient number, since it is larger than the sum of its proper divisors (1).

218261903 is an equidigital number, since it uses as much as digits as its factorization.

218261903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 218261903 is about 14773.6895527150. The cubic root of 218261903 is about 602.0870863296.

Subtracting 218261903 from its reverse (309162812), we obtain a palindrome (90900909).

The spelling of 218261903 in words is "two hundred eighteen million, two hundred sixty-one thousand, nine hundred three".