1313506521 has 12 divisors (see below), whose sum is σ = 1902728100. Its totient is φ = 873159840.

The previous prime is 1313506507. The next prime is 1313506553. The reversal of 1313506521 is 1256053131.

1313506521 is a `hidden beast` number, since 1 + 3 + 1 + 3 + 5 + 0 + 652 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 977187600 + 336318921 = 31260^2 + 18339^2 .

It is not a de Polignac number, because 1313506521 - 2⁵ = 1313506489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1313506501) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 205950 + ... + 212231.

It is an arithmetic number, because the mean of its divisors is an integer number (158560675).

Almost surely, 2^1313506521 is an apocalyptic number.

It is an amenable number.

1313506521 is a deficient number, since it is larger than the sum of its proper divisors (589221579).

1313506521 is a wasteful number, since it uses less digits than its factorization.

1313506521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 418536 (or 418533 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 1313506521 is about 36242.3305128133. The cubic root of 1313506521 is about 1095.1595914261.

Adding to 1313506521 its reverse (1256053131), we get a palindrome (2569559652).

The spelling of 1313506521 in words is "one billion, three hundred thirteen million, five hundred six thousand, five hundred twenty-one".