18728718 has 32 divisors (see below), whose sum is σ = 40400640. Its totient is φ = 5768640.

The previous prime is 18728683. The next prime is 18728729. The reversal of 18728718 is 81782781.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18728718.

It is a congruent 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 15 ways as a sum of consecutive naturals, for example, 2671 + ... + 6677.

It is an arithmetic number, because the mean of its divisors is an integer number (1262520).

Almost surely, 2^18728718 is an apocalyptic number.

18728718 is an abundant number, since it is smaller than the sum of its proper divisors (21671922).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18728718 is a wasteful number, since it uses less digits than its factorization.

18728718 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4072.

The product of its digits is 50176, while the sum is 42.

The square root of 18728718 is about 4327.6688875190. The cubic root of 18728718 is about 265.5640909109.

The spelling of 18728718 in words is "eighteen million, seven hundred twenty-eight thousand, seven hundred eighteen".