16800409 has 2 divisors, whose sum is σ = 16800410. Its totient is φ = 16800408.

The previous prime is 16800397. The next prime is 16800431. The reversal of 16800409 is 90400861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16040025 + 760384 = 4005^2 + 872^2 .

It is a cyclic number.

It is not a de Polignac number, because 16800409 - 2⁹ = 16799897 is a prime.

It is not a weakly prime, because it can be changed into another prime (16801409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8400204 + 8400205.

It is an arithmetic number, because the mean of its divisors is an integer number (8400205).

Almost surely, 2^16800409 is an apocalyptic number.

It is an amenable number.

16800409 is a deficient number, since it is larger than the sum of its proper divisors (1).

16800409 is an equidigital number, since it uses as much as digits as its factorization.

16800409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 16800409 is about 4098.8301989714. The cubic root of 16800409 is about 256.1179113809.

The spelling of 16800409 in words is "sixteen million, eight hundred thousand, four hundred nine".