18990599 has 2 divisors, whose sum is σ = 18990600. Its totient is φ = 18990598.

The previous prime is 18990541. The next prime is 18990607. The reversal of 18990599 is 99509981.

It is a strong prime.

It is an emirp because it is prime and its reverse (99509981) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18990599 is a prime.

It is a Sophie Germain 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 (18990539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9495299 + 9495300.

It is an arithmetic number, because the mean of its divisors is an integer number (9495300).

Almost surely, 2^18990599 is an apocalyptic number.

18990599 is a deficient number, since it is larger than the sum of its proper divisors (1).

18990599 is an equidigital number, since it uses as much as digits as its factorization.

18990599 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 262440, while the sum is 50.

The square root of 18990599 is about 4357.8204414592. The cubic root of 18990599 is about 266.7961477101.

The spelling of 18990599 in words is "eighteen million, nine hundred ninety thousand, five hundred ninety-nine".