918985 has 4 divisors (see below), whose sum is σ = 1102788. Its totient is φ = 735184.

The previous prime is 918971. The next prime is 918989. The reversal of 918985 is 589819.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 589819 = 281 ⋅2099.

It can be written as a sum of positive squares in 2 ways, for example, as 383161 + 535824 = 619^2 + 732^2 .

It is a cyclic number.

It is not a de Polignac number, because 918985 - 2⁷ = 918857 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

918985 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (918989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91894 + ... + 91903.

It is an arithmetic number, because the mean of its divisors is an integer number (275697).

2⁹¹⁸⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

918985 is a deficient number, since it is larger than the sum of its proper divisors (183803).

918985 is a wasteful number, since it uses less digits than its factorization.

918985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183802.

The product of its digits is 25920, while the sum is 40.

The square root of 918985 is about 958.6370533210. The cubic root of 918985 is about 97.2231021538.

The spelling of 918985 in words is "nine hundred eighteen thousand, nine hundred eighty-five".