18974399 has 2 divisors, whose sum is σ = 18974400. Its totient is φ = 18974398.

The previous prime is 18974383. The next prime is 18974413. The reversal of 18974399 is 99347981.

It is a strong prime.

It is an emirp because it is prime and its reverse (99347981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18974399 - 2⁴ = 18974383 is a prime.

It is a super-2 number, since 2×18974399² = 720055634822402, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18974339) 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, 9487199 + 9487200.

It is an arithmetic number, because the mean of its divisors is an integer number (9487200).

Almost surely, 2^18974399 is an apocalyptic number.

18974399 is a deficient number, since it is larger than the sum of its proper divisors (1).

18974399 is an equidigital number, since it uses as much as digits as its factorization.

18974399 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 489888, while the sum is 50.

The square root of 18974399 is about 4355.9613175509. The cubic root of 18974399 is about 266.7202623177.

The spelling of 18974399 in words is "eighteen million, nine hundred seventy-four thousand, three hundred ninety-nine".