521245513 has 4 divisors (see below), whose sum is σ = 531080388. Its totient is φ = 511410640.

The previous prime is 521245489. The next prime is 521245519. The reversal of 521245513 is 315542125.

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 204690249 + 316555264 = 14307^2 + 17792^2 .

It is a cyclic number.

It is not a de Polignac number, because 521245513 - 2⁹ = 521245001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521245519) 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, 4917358 + ... + 4917463.

It is an arithmetic number, because the mean of its divisors is an integer number (132770097).

Almost surely, 2^521245513 is an apocalyptic number.

521245513 is a gapful number since it is divisible by the number (53) formed by its first and last digit.

It is an amenable number.

521245513 is a deficient number, since it is larger than the sum of its proper divisors (9834875).

521245513 is an equidigital number, since it uses as much as digits as its factorization.

521245513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9834874.

The product of its digits is 6000, while the sum is 28.

The square root of 521245513 is about 22830.8018475042. The cubic root of 521245513 is about 804.7866739235.

Adding to 521245513 its reverse (315542125), we get a palindrome (836787638).

The spelling of 521245513 in words is "five hundred twenty-one million, two hundred forty-five thousand, five hundred thirteen".