18516985 has 8 divisors (see below), whose sum is σ = 22283136. Its totient is φ = 14771760.

The previous prime is 18516947. The next prime is 18516989. The reversal of 18516985 is 58961581.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18516985 - 2¹⁹ = 17992697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18516989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3211 + ... + 6880.

It is an arithmetic number, because the mean of its divisors is an integer number (2785392).

Almost surely, 2^18516985 is an apocalyptic number.

It is an amenable number.

18516985 is a deficient number, since it is larger than the sum of its proper divisors (3766151).

18516985 is a wasteful number, since it uses less digits than its factorization.

18516985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10463.

The product of its digits is 86400, while the sum is 43.

The square root of 18516985 is about 4303.1366466800. The cubic root of 18516985 is about 264.5595388664.

It can be divided in two parts, 1851 and 6985, that added together give a square (8836 = 94²).

The spelling of 18516985 in words is "eighteen million, five hundred sixteen thousand, nine hundred eighty-five".