18135866 has 16 divisors (see below), whose sum is σ = 31280256. Its totient is φ = 7724976.

The previous prime is 18135853. The next prime is 18135881. The reversal of 18135866 is 66853181.

It is a happy number.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 1541 + ... + 6216.

It is an arithmetic number, because the mean of its divisors is an integer number (1955016).

Almost surely, 2^18135866 is an apocalyptic number.

18135866 is a deficient number, since it is larger than the sum of its proper divisors (13144390).

18135866 is a wasteful number, since it uses less digits than its factorization.

18135866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7933.

The product of its digits is 34560, while the sum is 38.

The square root of 18135866 is about 4258.6225472563. The cubic root of 18135866 is about 262.7318755391.

The spelling of 18135866 in words is "eighteen million, one hundred thirty-five thousand, eight hundred sixty-six".