404213421421 has 4 divisors (see below), whose sum is σ = 404412641500. Its totient is φ = 404014201344.

The previous prime is 404213421413. The next prime is 404213421449. The reversal of 404213421421 is 124124312404.

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 300757915396 + 103455506025 = 548414^2 + 321645^2 .

It is a cyclic number.

It is not a de Polignac number, because 404213421421 - 2³ = 404213421413 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 404213421421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (404213421121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99606996 + ... + 99611053.

It is an arithmetic number, because the mean of its divisors is an integer number (101103160375).

Almost surely, 2^404213421421 is an apocalyptic number.

It is an amenable number.

404213421421 is a deficient number, since it is larger than the sum of its proper divisors (199220079).

404213421421 is a wasteful number, since it uses less digits than its factorization.

404213421421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199220078.

The product of its (nonzero) digits is 6144, while the sum is 28.

Adding to 404213421421 its reverse (124124312404), we get a palindrome (528337733825).

The spelling of 404213421421 in words is "four hundred four billion, two hundred thirteen million, four hundred twenty-one thousand, four hundred twenty-one".