12409391 has 2 divisors, whose sum is σ = 12409392. Its totient is φ = 12409390.

The previous prime is 12409387. The next prime is 12409421. The reversal of 12409391 is 19390421.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12409391 - 2² = 12409387 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12409381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6204695 + 6204696.

It is an arithmetic number, because the mean of its divisors is an integer number (6204696).

Almost surely, 2^12409391 is an apocalyptic number.

12409391 is a deficient number, since it is larger than the sum of its proper divisors (1).

12409391 is an equidigital number, since it uses as much as digits as its factorization.

12409391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 12409391 is about 3522.6965523587. The cubic root of 12409391 is about 231.5173216377.

The spelling of 12409391 in words is "twelve million, four hundred nine thousand, three hundred ninety-one".