985591 has 4 divisors (see below), whose sum is σ = 990792. Its totient is φ = 980392.

The previous prime is 985571. The next prime is 985597. The reversal of 985591 is 195589.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 195589 = 317 ⋅617.

It is a cyclic number.

It is not a de Polignac number, because 985591 - 2⁷ = 985463 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 985591.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (985597) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 2305 + ... + 2698.

It is an arithmetic number, because the mean of its divisors is an integer number (247698).

2⁹⁸⁵⁵⁹¹ is an apocalyptic number.

985591 is a deficient number, since it is larger than the sum of its proper divisors (5201).

985591 is a wasteful number, since it uses less digits than its factorization.

985591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5200.

The product of its digits is 16200, while the sum is 37.

The square root of 985591 is about 992.7693589147. The cubic root of 985591 is about 99.5173744732.

The spelling of 985591 in words is "nine hundred eighty-five thousand, five hundred ninety-one".