12815513 has 4 divisors (see below), whose sum is σ = 12836148. Its totient is φ = 12794880.

The previous prime is 12815503. The next prime is 12815533. The reversal of 12815513 is 31551821.

It is a happy number.

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 9815689 + 2999824 = 3133^2 + 1732^2 .

It is a cyclic number.

It is not a de Polignac number, because 12815513 - 2²² = 8621209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12815503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9356 + ... + 10637.

It is an arithmetic number, because the mean of its divisors is an integer number (3209037).

Almost surely, 2^12815513 is an apocalyptic number.

It is an amenable number.

12815513 is a deficient number, since it is larger than the sum of its proper divisors (20635).

12815513 is an equidigital number, since it uses as much as digits as its factorization.

12815513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20634.

The product of its digits is 1200, while the sum is 26.

The square root of 12815513 is about 3579.8761151749. The cubic root of 12815513 is about 234.0158815042.

The spelling of 12815513 in words is "twelve million, eight hundred fifteen thousand, five hundred thirteen".