581660 has 24 divisors (see below), whose sum is σ = 1236480. Its totient is φ = 229824.

The previous prime is 581657. The next prime is 581663. The reversal of 581660 is 66185.

It is an interprime number because it is at equal distance from previous prime (581657) and next prime (581663).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (581663) 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 7 ways as a sum of consecutive naturals, for example, 2426 + ... + 2654.

It is an arithmetic number, because the mean of its divisors is an integer number (51520).

2⁵⁸¹⁶⁶⁰ is an apocalyptic number.

It is an amenable number.

581660 is an abundant number, since it is smaller than the sum of its proper divisors (654820).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

581660 is a wasteful number, since it uses less digits than its factorization.

581660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365 (or 363 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 581660 is about 762.6663752913. Note that the first 3 decimals coincide. The cubic root of 581660 is about 83.4749946041.

The spelling of 581660 in words is "five hundred eighty-one thousand, six hundred sixty".