220581 has 6 divisors (see below), whose sum is σ = 318630. Its totient is φ = 147048.

The previous prime is 220579. The next prime is 220589. The reversal of 220581 is 185022.

It can be written as a sum of positive squares in only one way, i.e., 216225 + 4356 = 465^2 + 66^2 .

It is not a de Polignac number, because 220581 - 2¹ = 220579 is a prime.

It is a super-2 number, since 2×220581² = 97311955122, which contains 22 as substring.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12246 + ... + 12263.

It is an arithmetic number, because the mean of its divisors is an integer number (53105).

2²²⁰⁵⁸¹ is an apocalyptic number.

It is an amenable number.

220581 is a deficient number, since it is larger than the sum of its proper divisors (98049).

220581 is a wasteful number, since it uses less digits than its factorization.

220581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24515 (or 24512 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 220581 is about 469.6605156919. The cubic root of 220581 is about 60.4212028831.

The spelling of 220581 in words is "two hundred twenty thousand, five hundred eighty-one".