16784009 has 4 divisors (see below), whose sum is σ = 18309840. Its totient is φ = 15258180.

The previous prime is 16783993. The next prime is 16784021. The reversal of 16784009 is 90048761.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90048761 = 11 ⋅8186251.

It is a cyclic number.

It is not a de Polignac number, because 16784009 - 2⁴ = 16783993 is a prime.

It is a super-2 number, since 2×16784009² = 563405916224162, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 16784009.

It is not an unprimeable number, because it can be changed into a prime (16784039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 762899 + ... + 762920.

It is an arithmetic number, because the mean of its divisors is an integer number (4577460).

Almost surely, 2^16784009 is an apocalyptic number.

It is an amenable number.

16784009 is a deficient number, since it is larger than the sum of its proper divisors (1525831).

16784009 is a wasteful number, since it uses less digits than its factorization.

16784009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1525830.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 16784009 is about 4096.8291397128. The cubic root of 16784009 is about 256.0345463226.

The spelling of 16784009 in words is "sixteen million, seven hundred eighty-four thousand, nine".