18690005 has 4 divisors (see below), whose sum is σ = 22428012. Its totient is φ = 14952000.

The previous prime is 18689989. The next prime is 18690019. The reversal of 18690005 is 50009681.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2617924 + 16072081 = 1618^2 + 4009^2 .

It is not a de Polignac number, because 18690005 - 2⁴ = 18689989 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18690005.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1868996 + ... + 1869005.

It is an arithmetic number, because the mean of its divisors is an integer number (5607003).

Almost surely, 2^18690005 is an apocalyptic number.

It is an amenable number.

18690005 is a deficient number, since it is larger than the sum of its proper divisors (3738007).

18690005 is an equidigital number, since it uses as much as digits as its factorization.

18690005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3738006.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 18690005 is about 4323.1938425197. The cubic root of 18690005 is about 265.3809875365.

Adding to 18690005 its reverse (50009681), we get a palindrome (68699686).

The spelling of 18690005 in words is "eighteen million, six hundred ninety thousand, five".