521321413 has 4 divisors (see below), whose sum is σ = 521367660. Its totient is φ = 521275168.

The previous prime is 521321407. The next prime is 521321417. The reversal of 521321413 is 314123125.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 129004164 + 392317249 = 11358^2 + 19807^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-521321413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521321417) 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, 6081 + ... + 32857.

It is an arithmetic number, because the mean of its divisors is an integer number (130341915).

Almost surely, 2^521321413 is an apocalyptic number.

It is an amenable number.

521321413 is a deficient number, since it is larger than the sum of its proper divisors (46247).

521321413 is a wasteful number, since it uses less digits than its factorization.

521321413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46246.

The product of its digits is 720, while the sum is 22.

The square root of 521321413 is about 22832.4640150817. The cubic root of 521321413 is about 804.8257344317.

Adding to 521321413 its reverse (314123125), we get a palindrome (835444538).

The spelling of 521321413 in words is "five hundred twenty-one million, three hundred twenty-one thousand, four hundred thirteen".