18493903 has 2 divisors, whose sum is σ = 18493904. Its totient is φ = 18493902.

The previous prime is 18493883. The next prime is 18493907. The reversal of 18493903 is 30939481.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18493903 - 2¹⁷ = 18362831 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18493907) 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, 9246951 + 9246952.

It is an arithmetic number, because the mean of its divisors is an integer number (9246952).

Almost surely, 2^18493903 is an apocalyptic number.

18493903 is a deficient number, since it is larger than the sum of its proper divisors (1).

18493903 is an equidigital number, since it uses as much as digits as its factorization.

18493903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 18493903 is about 4300.4538132620. The cubic root of 18493903 is about 264.4495659168.

The spelling of 18493903 in words is "eighteen million, four hundred ninety-three thousand, nine hundred three".