521243613 has 32 divisors (see below), whose sum is σ = 891976320. Its totient is φ = 297319680.

The previous prime is 521243539. The next prime is 521243623. The reversal of 521243613 is 316342125.

521243613 is a `hidden beast` number, since 5 + 2 + 1 + 2 + 43 + 613 = 666.

It is not a de Polignac number, because 521243613 - 2⁹ = 521243101 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521243623) 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 31 ways as a sum of consecutive naturals, for example, 46570 + ... + 56667.

It is an arithmetic number, because the mean of its divisors is an integer number (27874260).

Almost surely, 2^521243613 is an apocalyptic number.

It is an amenable number.

521243613 is a deficient number, since it is larger than the sum of its proper divisors (370732707).

521243613 is a wasteful number, since it uses less digits than its factorization.

521243613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103274 (or 103268 counting only the distinct ones).

The product of its digits is 4320, while the sum is 27.

The square root of 521243613 is about 22830.7602370136. The cubic root of 521243613 is about 804.7856960756.

Adding to 521243613 its reverse (316342125), we get a palindrome (837585738).

The spelling of 521243613 in words is "five hundred twenty-one million, two hundred forty-three thousand, six hundred thirteen".