18336391 has 2 divisors, whose sum is σ = 18336392. Its totient is φ = 18336390.

The previous prime is 18336377. The next prime is 18336467. The reversal of 18336391 is 19363381.

It is a weak prime.

It is an emirp because it is prime and its reverse (19363381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18336391 - 2¹³ = 18328199 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18336301) 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, 9168195 + 9168196.

It is an arithmetic number, because the mean of its divisors is an integer number (9168196).

Almost surely, 2^18336391 is an apocalyptic number.

18336391 is a deficient number, since it is larger than the sum of its proper divisors (1).

18336391 is an equidigital number, since it uses as much as digits as its factorization.

18336391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11664, while the sum is 34.

The square root of 18336391 is about 4282.1012365426. The cubic root of 18336391 is about 263.6966547549.

The spelling of 18336391 in words is "eighteen million, three hundred thirty-six thousand, three hundred ninety-one".