18027399 has 36 divisors (see below), whose sum is σ = 27621288. Its totient is φ = 10445760.

The previous prime is 18027379. The next prime is 18027403. The reversal of 18027399 is 99372081.

It is not a de Polignac number, because 18027399 - 2⁷ = 18027271 is a prime.

It is a super-2 number, since 2×18027399² = 649974229410402, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18027319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 487209 + ... + 487245.

It is an arithmetic number, because the mean of its divisors is an integer number (767258).

Almost surely, 2^18027399 is an apocalyptic number.

18027399 is a deficient number, since it is larger than the sum of its proper divisors (9593889).

18027399 is a wasteful number, since it uses less digits than its factorization.

18027399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128 (or 84 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 18027399 is about 4245.8684623997. The cubic root of 18027399 is about 262.2070455150.

18027399 divided by its sum of digits (39) gives a triangular number (462241 = T₉₆₁).

The spelling of 18027399 in words is "eighteen million, twenty-seven thousand, three hundred ninety-nine".