12400009 has 2 divisors, whose sum is σ = 12400010. Its totient is φ = 12400008.

The previous prime is 12400001. The next prime is 12400043. The reversal of 12400009 is 90000421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9903609 + 2496400 = 3147^2 + 1580^2 .

It is a cyclic number.

It is not a de Polignac number, because 12400009 - 2³ = 12400001 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12399965 and 12400001.

It is not a weakly prime, because it can be changed into another prime (12400001) 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, 6200004 + 6200005.

It is an arithmetic number, because the mean of its divisors is an integer number (6200005).

Almost surely, 2^12400009 is an apocalyptic number.

It is an amenable number.

12400009 is a deficient number, since it is larger than the sum of its proper divisors (1).

12400009 is an equidigital number, since it uses as much as digits as its factorization.

12400009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 12400009 is about 3521.3646502457. The cubic root of 12400009 is about 231.4589614507.

The spelling of 12400009 in words is "twelve million, four hundred thousand, nine".