809561513 has 4 divisors (see below), whose sum is σ = 809994240. Its totient is φ = 809128788.

The previous prime is 809561509. The next prime is 809561527. The reversal of 809561513 is 315165908.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 809561513 - 2² = 809561509 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (809560513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 213545 + ... + 217302.

It is an arithmetic number, because the mean of its divisors is an integer number (202498560).

Almost surely, 2^809561513 is an apocalyptic number.

It is an amenable number.

809561513 is a deficient number, since it is larger than the sum of its proper divisors (432727).

809561513 is a wasteful number, since it uses less digits than its factorization.

809561513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432726.

The product of its (nonzero) digits is 32400, while the sum is 38.

The square root of 809561513 is about 28452.7944673278. The cubic root of 809561513 is about 932.0015138862.

The spelling of 809561513 in words is "eight hundred nine million, five hundred sixty-one thousand, five hundred thirteen".