521421313 has 16 divisors (see below), whose sum is σ = 642579840. Its totient is φ = 413078400.

The previous prime is 521421289. The next prime is 521421319. The reversal of 521421313 is 313124125.

It is a happy number.

It is not a de Polignac number, because 521421313 - 2¹⁷ = 521290241 is a prime.

It is not an unprimeable number, because it can be changed into a prime (521421319) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42358 + ... + 53263.

It is an arithmetic number, because the mean of its divisors is an integer number (40161240).

Almost surely, 2^521421313 is an apocalyptic number.

It is an amenable number.

521421313 is a deficient number, since it is larger than the sum of its proper divisors (121158527).

521421313 is a wasteful number, since it uses less digits than its factorization.

521421313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95688.

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

The square root of 521421313 is about 22834.6515848173. The cubic root of 521421313 is about 804.8771403102.

Adding to 521421313 its reverse (313124125), we get a palindrome (834545438).

The spelling of 521421313 in words is "five hundred twenty-one million, four hundred twenty-one thousand, three hundred thirteen".