16819909 has 2 divisors, whose sum is σ = 16819910. Its totient is φ = 16819908.

The previous prime is 16819889. The next prime is 16819927. The reversal of 16819909 is 90991861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16728100 + 91809 = 4090^2 + 303^2 .

It is an emirp because it is prime and its reverse (90991861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16819909 - 2¹¹ = 16817861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16819109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8409954 + 8409955.

It is an arithmetic number, because the mean of its divisors is an integer number (8409955).

Almost surely, 2^16819909 is an apocalyptic number.

It is an amenable number.

16819909 is a deficient number, since it is larger than the sum of its proper divisors (1).

16819909 is an equidigital number, since it uses as much as digits as its factorization.

16819909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34992, while the sum is 43.

The square root of 16819909 is about 4101.2082366054. The cubic root of 16819909 is about 256.2169638950.

The spelling of 16819909 in words is "sixteen million, eight hundred nineteen thousand, nine hundred nine".