18281903 has 2 divisors, whose sum is σ = 18281904. Its totient is φ = 18281902.

The previous prime is 18281867. The next prime is 18281911. The reversal of 18281903 is 30918281.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18281903 - 2⁶ = 18281839 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18281903.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18281983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9140951 + 9140952.

It is an arithmetic number, because the mean of its divisors is an integer number (9140952).

Almost surely, 2^18281903 is an apocalyptic number.

18281903 is a deficient number, since it is larger than the sum of its proper divisors (1).

18281903 is an equidigital number, since it uses as much as digits as its factorization.

18281903 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 18281903 is about 4275.7342059581. The cubic root of 18281903 is about 263.4351972878.

The spelling of 18281903 in words is "eighteen million, two hundred eighty-one thousand, nine hundred three".