12800009 has 2 divisors, whose sum is σ = 12800010. Its totient is φ = 12800008.

The previous prime is 12799987. The next prime is 12800017. The reversal of 12800009 is 90000821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10465225 + 2334784 = 3235^2 + 1528^2 .

It is an emirp because it is prime and its reverse (90000821) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12800009 is a prime.

It is not a weakly prime, because it can be changed into another prime (12800209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6400004 + 6400005.

It is an arithmetic number, because the mean of its divisors is an integer number (6400005).

Almost surely, 2^12800009 is an apocalyptic number.

It is an amenable number.

12800009 is a deficient number, since it is larger than the sum of its proper divisors (1).

12800009 is an equidigital number, since it uses as much as digits as its factorization.

12800009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 12800009 is about 3577.7100217877. The cubic root of 12800009 is about 233.9214738823.

The spelling of 12800009 in words is "twelve million, eight hundred thousand, nine".