404581 has 6 divisors (see below), whose sum is σ = 419046. Its totient is φ = 390600.

The previous prime is 404557. The next prime is 404597. The reversal of 404581 is 185404.

It can be written as a sum of positive squares in only one way, i.e., 216225 + 188356 = 465^2 + 434^2 .

It is a de Polignac number, because none of the positive numbers 2^k-404581 is a prime.

It is a super-2 number, since 2×404581² = 327371571122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (404531) 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, 751 + ... + 1171.

It is an arithmetic number, because the mean of its divisors is an integer number (69841).

2⁴⁰⁴⁵⁸¹ is an apocalyptic number.

It is an amenable number.

404581 is a deficient number, since it is larger than the sum of its proper divisors (14465).

404581 is an equidigital number, since it uses as much as digits as its factorization.

404581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 483 (or 452 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 404581 is about 636.0668203892. The cubic root of 404581 is about 73.9608387875.

Adding to 404581 its reverse (185404), we get a palindrome (589985).

It can be divided in two parts, 4045 and 81, that multiplied together give a triangular number (327645 = T₈₀₉).

The spelling of 404581 in words is "four hundred four thousand, five hundred eighty-one".