18988199 has 2 divisors, whose sum is σ = 18988200. Its totient is φ = 18988198.

The previous prime is 18988183. The next prime is 18988217. The reversal of 18988199 is 99188981.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18988199 - 2⁴ = 18988183 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18988199.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18981199) 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, 9494099 + 9494100.

It is an arithmetic number, because the mean of its divisors is an integer number (9494100).

Almost surely, 2^18988199 is an apocalyptic number.

18988199 is a deficient number, since it is larger than the sum of its proper divisors (1).

18988199 is an equidigital number, since it uses as much as digits as its factorization.

18988199 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 373248, while the sum is 53.

The square root of 18988199 is about 4357.5450657452. The cubic root of 18988199 is about 266.7849081536.

It can be divided in two parts, 189 and 88199, that added together give a palindrome (88388).

The spelling of 18988199 in words is "eighteen million, nine hundred eighty-eight thousand, one hundred ninety-nine".