404042321 has 4 divisors (see below), whose sum is σ = 404337972. Its totient is φ = 403746672.

The previous prime is 404042299. The next prime is 404042339. The reversal of 404042321 is 123240404.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 306250000 + 97792321 = 17500^2 + 9889^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-404042321 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 404042293 and 404042302.

It is not an unprimeable number, because it can be changed into a prime (404042021) 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, 145766 + ... + 148511.

It is an arithmetic number, because the mean of its divisors is an integer number (101084493).

Almost surely, 2^404042321 is an apocalyptic number.

It is an amenable number.

404042321 is a deficient number, since it is larger than the sum of its proper divisors (295651).

404042321 is a wasteful number, since it uses less digits than its factorization.

404042321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295650.

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 404042321 is about 20100.8039888956. The cubic root of 404042321 is about 739.2799917817.

Adding to 404042321 its reverse (123240404), we get a palindrome (527282725).

The spelling of 404042321 in words is "four hundred four million, forty-two thousand, three hundred twenty-one".