18481999 has 2 divisors, whose sum is σ = 18482000. Its totient is φ = 18481998.

The previous prime is 18481997. The next prime is 18482033. The reversal of 18481999 is 99918481.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18481999 - 2¹ = 18481997 is a prime.

Together with 18481997, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18481997) 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 as a sum of consecutive naturals, namely, 9240999 + 9241000.

It is an arithmetic number, because the mean of its divisors is an integer number (9241000).

Almost surely, 2^18481999 is an apocalyptic number.

18481999 is a deficient number, since it is larger than the sum of its proper divisors (1).

18481999 is an equidigital number, since it uses as much as digits as its factorization.

18481999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 49.

The square root of 18481999 is about 4299.0695504958. The cubic root of 18481999 is about 264.3928141808.

The spelling of 18481999 in words is "eighteen million, four hundred eighty-one thousand, nine hundred ninety-nine".