531985 has 4 divisors (see below), whose sum is σ = 638388. Its totient is φ = 425584.

The previous prime is 531983. The next prime is 531989. The reversal of 531985 is 589135.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 410881 + 121104 = 641^2 + 348^2 .

It is a cyclic number.

It is not a de Polignac number, because 531985 - 2¹ = 531983 is a prime.

It is a Smith number, since the sum of its digits (31) 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.

It is not an unprimeable number, because it can be changed into a prime (531983) 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, 53194 + ... + 53203.

It is an arithmetic number, because the mean of its divisors is an integer number (159597).

2⁵³¹⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

531985 is a deficient number, since it is larger than the sum of its proper divisors (106403).

531985 is a wasteful number, since it uses less digits than its factorization.

531985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106402.

The product of its digits is 5400, while the sum is 31.

The square root of 531985 is about 729.3730184206. The cubic root of 531985 is about 81.0276286383.

The spelling of 531985 in words is "five hundred thirty-one thousand, nine hundred eighty-five".