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BaseRepresentation
bin1111011001
31100111
433121
512420
64321
72605
oct1731
91314
10985
11816
126a1
135aa
14505
1545a
hex3d9

985 has 4 divisors (see below), whose sum is σ = 1188. Its totient is φ = 784.

The previous prime is 983. The next prime is 991. The reversal of 985 is 589.

Subtracting from 985 its product of digits (360), we obtain a 4-th power (625 = 54).

985 = 52 + 62 + ... + 142.

985 is nontrivially palindromic in base 14.

985 is an esthetic number in base 6, because in such base its adjacent digits differ by 1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 589 = 1931.

It can be written as a sum of positive squares in 2 ways, for example, as 729 + 256 = 27^2 + 16^2 .

It is a cyclic number.

It is not a de Polignac number, because 985 - 21 = 983 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

985 is an undulating number in base 14.

It is a plaindrome in base 13 and base 15.

It is a nialpdrome in base 6 and base 10.

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 94 + ... + 103.

It is an arithmetic number, because the mean of its divisors is an integer number (297).

2985 is an apocalyptic number.

It is an amenable number.

985 is a deficient number, since it is larger than the sum of its proper divisors (203).

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

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

The sum of its prime factors is 202.

The product of its digits is 360, while the sum is 22.

The square root of 985 is about 31.3847096530. The cubic root of 985 is about 9.9497478956.

The spelling of 985 in words is "nine hundred eighty-five", and thus it is an aban number and an oban number.

Divisors: 1 5 197 985