404012321521 has 4 divisors (see below), whose sum is σ = 414931573492. Its totient is φ = 393093069552.

The previous prime is 404012321443. The next prime is 404012321539. The reversal of 404012321521 is 125123210404.

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 273863822400 + 130148499121 = 523320^2 + 360761^2 .

It is a cyclic number.

It is not a de Polignac number, because 404012321521 - 2⁷ = 404012321393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (404012321221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5459625930 + ... + 5459626003.

It is an arithmetic number, because the mean of its divisors is an integer number (103732893373).

Almost surely, 2^404012321521 is an apocalyptic number.

It is an amenable number.

404012321521 is a deficient number, since it is larger than the sum of its proper divisors (10919251971).

404012321521 is a wasteful number, since it uses less digits than its factorization.

404012321521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10919251970.

The product of its (nonzero) digits is 1920, while the sum is 25.

Adding to 404012321521 its reverse (125123210404), we get a palindrome (529135531925).

The spelling of 404012321521 in words is "four hundred four billion, twelve million, three hundred twenty-one thousand, five hundred twenty-one".