18247399 has 2 divisors, whose sum is σ = 18247400. Its totient is φ = 18247398.

The previous prime is 18247381. The next prime is 18247451. The reversal of 18247399 is 99374281.

It is a weak prime.

It is an emirp because it is prime and its reverse (99374281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18247399 - 2¹⁵ = 18214631 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18247309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9123699 + 9123700.

It is an arithmetic number, because the mean of its divisors is an integer number (9123700).

Almost surely, 2^18247399 is an apocalyptic number.

18247399 is a deficient number, since it is larger than the sum of its proper divisors (1).

18247399 is an equidigital number, since it uses as much as digits as its factorization.

18247399 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 43.

The square root of 18247399 is about 4271.6974377875. The cubic root of 18247399 is about 263.2693631221.

The spelling of 18247399 in words is "eighteen million, two hundred forty-seven thousand, three hundred ninety-nine".