13855409 has 2 divisors, whose sum is σ = 13855410. Its totient is φ = 13855408.

The previous prime is 13855403. The next prime is 13855411. The reversal of 13855409 is 90455831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10543009 + 3312400 = 3247^2 + 1820^2 .

It is an emirp because it is prime and its reverse (90455831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13855409 - 2⁴ = 13855393 is a prime.

It is a Sophie Germain prime.

Together with 13855411, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (13855403) 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, 6927704 + 6927705.

It is an arithmetic number, because the mean of its divisors is an integer number (6927705).

Almost surely, 2^13855409 is an apocalyptic number.

It is an amenable number.

13855409 is a deficient number, since it is larger than the sum of its proper divisors (1).

13855409 is an equidigital number, since it uses as much as digits as its factorization.

13855409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 13855409 is about 3722.2854538576. The cubic root of 13855409 is about 240.1816275592.

The spelling of 13855409 in words is "thirteen million, eight hundred fifty-five thousand, four hundred nine".