18681005 has 12 divisors (see below), whose sum is σ = 26077500. Its totient is φ = 12809664.

The previous prime is 18680999. The next prime is 18681029. The reversal of 18681005 is 50018681.

It can be written as a sum of positive squares in 2 ways, for example, as 8934121 + 9746884 = 2989^2 + 3122^2 .

It is not a de Polignac number, because 18681005 - 2⁴ = 18680989 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 37880 + ... + 38369.

It is an arithmetic number, because the mean of its divisors is an integer number (2173125).

Almost surely, 2^18681005 is an apocalyptic number.

It is an amenable number.

18681005 is a deficient number, since it is larger than the sum of its proper divisors (7396495).

18681005 is an equidigital number, since it uses as much as digits as its factorization.

18681005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76268 (or 76261 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 29.

The square root of 18681005 is about 4322.1528200655. The cubic root of 18681005 is about 265.3383834394.

Adding to 18681005 its reverse (50018681), we get a palindrome (68699686).

The spelling of 18681005 in words is "eighteen million, six hundred eighty-one thousand, five".