18504385 has 16 divisors (see below), whose sum is σ = 23601600.
Its totient is φ = 13887936.
The previous prime is 18504383. The next prime is 18504389. The reversal of 18504385 is 58340581.
It is not a de Polignac number, because 18504385 - 21 = 18504383 is a prime.
It is a self number, because there is not a number n which added to its sum of digits gives 18504385.
It is not an unprimeable number, because it can be changed into a prime (18504383) by changing a digit.
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, 9462 + ... + 11248.
It is an arithmetic number, because the mean of its divisors is an integer number (1475100).
Almost surely, 218504385 is an apocalyptic number.
It is an amenable number.
18504385 is a deficient number, since it is larger than the sum of its proper divisors (5097215).
18504385 is a wasteful number, since it uses less digits than its factorization.
18504385 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 1920.
The product of its (nonzero) digits is 19200, while the sum is 34.
The square root of 18504385 is about 4301.6723492149.
The cubic root of 18504385 is about 264.4995181779.
The spelling of 18504385 in words is "eighteen million, five hundred four thousand, three hundred eighty-five".