404031221 has 12 divisors (see below), whose sum is σ = 447360396. Its totient is φ = 364605120.

The previous prime is 404031211. The next prime is 404031227. The reversal of 404031221 is 122130404.

It can be written as a sum of positive squares in 2 ways, for example, as 181872196 + 222159025 = 13486^2 + 14905^2 .

It is not a de Polignac number, because 404031221 - 2¹⁸ = 403769077 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 404031221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (404031227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4391 + ... + 28763.

It is an arithmetic number, because the mean of its divisors is an integer number (37280033).

Almost surely, 2^404031221 is an apocalyptic number.

It is an amenable number.

404031221 is a deficient number, since it is larger than the sum of its proper divisors (43329175).

404031221 is a wasteful number, since it uses less digits than its factorization.

404031221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24532 (or 24521 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 404031221 is about 20100.5278786404. The cubic root of 404031221 is about 739.2732217953.

Adding to 404031221 its reverse (122130404), we get a palindrome (526161625).

The spelling of 404031221 in words is "four hundred four million, thirty-one thousand, two hundred twenty-one".