591561 has 6 divisors (see below), whose sum is σ = 854490. Its totient is φ = 394368.

The previous prime is 591559. The next prime is 591581. The reversal of 591561 is 165195.

It can be written as a sum of positive squares in only one way, i.e., 553536 + 38025 = 744^2 + 195^2 .

It is not a de Polignac number, because 591561 - 2¹ = 591559 is a prime.

It is an Ulam number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (591581) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 32856 + ... + 32873.

It is an arithmetic number, because the mean of its divisors is an integer number (142415).

2⁵⁹¹⁵⁶¹ is an apocalyptic number.

It is an amenable number.

591561 is a deficient number, since it is larger than the sum of its proper divisors (262929).

591561 is a wasteful number, since it uses less digits than its factorization.

591561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65735 (or 65732 counting only the distinct ones).

The product of its digits is 1350, while the sum is 27.

The square root of 591561 is about 769.1300280187. The cubic root of 591561 is about 83.9459686542.

The spelling of 591561 in words is "five hundred ninety-one thousand, five hundred sixty-one".