16806109409 has 2 divisors, whose sum is σ = 16806109410. Its totient is φ = 16806109408.

The previous prime is 16806109403. The next prime is 16806109511. The reversal of 16806109409 is 90490160861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8723560000 + 8082549409 = 93400^2 + 89903^2 .

It is an emirp because it is prime and its reverse (90490160861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16806109409 - 2⁸ = 16806109153 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16806109409.

It is not a weakly prime, because it can be changed into another prime (16806109403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8403054704 + 8403054705.

It is an arithmetic number, because the mean of its divisors is an integer number (8403054705).

Almost surely, 2^16806109409 is an apocalyptic number.

It is an amenable number.

16806109409 is a deficient number, since it is larger than the sum of its proper divisors (1).

16806109409 is an equidigital number, since it uses as much as digits as its factorization.

16806109409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 93312, while the sum is 44.

The spelling of 16806109409 in words is "sixteen billion, eight hundred six million, one hundred nine thousand, four hundred nine".