18299993 has 2 divisors, whose sum is σ = 18299994. Its totient is φ = 18299992.

The previous prime is 18299977. The next prime is 18300001. The reversal of 18299993 is 39999281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15031129 + 3268864 = 3877^2 + 1808^2 .

It is a cyclic number.

It is not a de Polignac number, because 18299993 - 2⁴ = 18299977 is a prime.

It is not a weakly prime, because it can be changed into another prime (18299903) 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, 9149996 + 9149997.

It is an arithmetic number, because the mean of its divisors is an integer number (9149997).

Almost surely, 2^18299993 is an apocalyptic number.

It is an amenable number.

18299993 is a deficient number, since it is larger than the sum of its proper divisors (1).

18299993 is an equidigital number, since it uses as much as digits as its factorization.

18299993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 314928, while the sum is 50.

The square root of 18299993 is about 4277.8491090734. The cubic root of 18299993 is about 263.5220586272.

The spelling of 18299993 in words is "eighteen million, two hundred ninety-nine thousand, nine hundred ninety-three".