12810509 has 4 divisors (see below), whose sum is σ = 12856380. Its totient is φ = 12764640.

The previous prime is 12810481. The next prime is 12810521. The reversal of 12810509 is 90501821.

It is a happy number.

12810509 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90501821 = 4099 ⋅22079.

It can be written as a sum of positive squares in 2 ways, for example, as 5654884 + 7155625 = 2378^2 + 2675^2 .

It is a cyclic number.

It is not a de Polignac number, because 12810509 - 2¹² = 12806413 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12810529) 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, 22514 + ... + 23075.

It is an arithmetic number, because the mean of its divisors is an integer number (3214095).

Almost surely, 2^12810509 is an apocalyptic number.

It is an amenable number.

12810509 is a deficient number, since it is larger than the sum of its proper divisors (45871).

12810509 is an equidigital number, since it uses as much as digits as its factorization.

12810509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45870.

The product of its (nonzero) digits is 720, while the sum is 26.

The square root of 12810509 is about 3579.1771400700. The cubic root of 12810509 is about 233.9854192585.

The spelling of 12810509 in words is "twelve million, eight hundred ten thousand, five hundred nine".