18128705 has 16 divisors (see below), whose sum is σ = 25536000. Its totient is φ = 12094272.

The previous prime is 18128687. The next prime is 18128729. The reversal of 18128705 is 50782181.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 18128705 - 2⁸ = 18128449 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5705 + ... + 8294.

It is an arithmetic number, because the mean of its divisors is an integer number (1596000).

Almost surely, 2^18128705 is an apocalyptic number.

It is an amenable number.

18128705 is a deficient number, since it is larger than the sum of its proper divisors (7407295).

18128705 is a wasteful number, since it uses less digits than its factorization.

18128705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14048.

The product of its (nonzero) digits is 4480, while the sum is 32.

The square root of 18128705 is about 4257.7816994299. The cubic root of 18128705 is about 262.6972908356.

The spelling of 18128705 in words is "eighteen million, one hundred twenty-eight thousand, seven hundred five".