18972199 has 2 divisors, whose sum is σ = 18972200. Its totient is φ = 18972198.

The previous prime is 18972193. The next prime is 18972229. The reversal of 18972199 is 99127981.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18972199 - 2⁷ = 18972071 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18972193) 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, 9486099 + 9486100.

It is an arithmetic number, because the mean of its divisors is an integer number (9486100).

Almost surely, 2^18972199 is an apocalyptic number.

18972199 is a deficient number, since it is larger than the sum of its proper divisors (1).

18972199 is an equidigital number, since it uses as much as digits as its factorization.

18972199 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 81648, while the sum is 46.

The square root of 18972199 is about 4355.7087827356. The cubic root of 18972199 is about 266.7099535633.

It can be divided in two parts, 1897 and 2199, that added together give a 12-th power (4096 = 2¹²).

The spelling of 18972199 in words is "eighteen million, nine hundred seventy-two thousand, one hundred ninety-nine".