12651809 has 2 divisors, whose sum is σ = 12651810. Its totient is φ = 12651808.

The previous prime is 12651803. The next prime is 12651833. The reversal of 12651809 is 90815621.

12651809 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10240000 + 2411809 = 3200^2 + 1553^2 .

It is a cyclic number.

It is not a de Polignac number, because 12651809 - 2²⁰ = 11603233 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12651803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6325904 + 6325905.

It is an arithmetic number, because the mean of its divisors is an integer number (6325905).

Almost surely, 2^12651809 is an apocalyptic number.

It is an amenable number.

12651809 is a deficient number, since it is larger than the sum of its proper divisors (1).

12651809 is an equidigital number, since it uses as much as digits as its factorization.

12651809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 12651809 is about 3556.9381495888. The cubic root of 12651809 is about 233.0151770401.

The spelling of 12651809 in words is "twelve million, six hundred fifty-one thousand, eight hundred nine".