12501809 has 2 divisors, whose sum is σ = 12501810. Its totient is φ = 12501808.

The previous prime is 12501803. The next prime is 12501821. The reversal of 12501809 is 90810521.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8880400 + 3621409 = 2980^2 + 1903^2 .

It is an emirp because it is prime and its reverse (90810521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12501809 - 2⁴ = 12501793 is a prime.

It is not a weakly prime, because it can be changed into another prime (12501803) 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 as a sum of consecutive naturals, namely, 6250904 + 6250905.

It is an arithmetic number, because the mean of its divisors is an integer number (6250905).

Almost surely, 2^12501809 is an apocalyptic number.

It is an amenable number.

12501809 is a deficient number, since it is larger than the sum of its proper divisors (1).

12501809 is an equidigital number, since it uses as much as digits as its factorization.

12501809 is an odious number, because the sum of its binary digits is odd.

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

The square root of 12501809 is about 3535.7897279109. The cubic root of 12501809 is about 232.0906366529.

The spelling of 12501809 in words is "twelve million, five hundred one thousand, eight hundred nine".