2205581 has 4 divisors (see below), whose sum is σ = 2520672. Its totient is φ = 1890492.

The previous prime is 2205551. The next prime is 2205587. The reversal of 2205581 is 1855022.

2205581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2205581 - 2¹⁰ = 2204557 is a prime.

It is a super-2 number, since 2×2205581² = 9729175095122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2205587) 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 3 ways as a sum of consecutive naturals, for example, 157535 + ... + 157548.

It is an arithmetic number, because the mean of its divisors is an integer number (630168).

2^2205581 is an apocalyptic number.

It is an amenable number.

2205581 is a deficient number, since it is larger than the sum of its proper divisors (315091).

2205581 is an equidigital number, since it uses as much as digits as its factorization.

2205581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315090.

The product of its (nonzero) digits is 800, while the sum is 23.

The square root of 2205581 is about 1485.1198604826. The cubic root of 2205581 is about 130.1690306182.

The spelling of 2205581 in words is "two million, two hundred five thousand, five hundred eighty-one".