18017899 has 2 divisors, whose sum is σ = 18017900. Its totient is φ = 18017898.

The previous prime is 18017897. The next prime is 18017911. The reversal of 18017899 is 99871081.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18017899 - 2¹ = 18017897 is a prime.

Together with 18017897, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (18017891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9008949 + 9008950.

It is an arithmetic number, because the mean of its divisors is an integer number (9008950).

Almost surely, 2^18017899 is an apocalyptic number.

18017899 is a deficient number, since it is larger than the sum of its proper divisors (1).

18017899 is an equidigital number, since it uses as much as digits as its factorization.

18017899 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 18017899 is about 4244.7495803640. The cubic root of 18017899 is about 262.1609785141.

The spelling of 18017899 in words is "eighteen million, seventeen thousand, eight hundred ninety-nine".