16785419509 has 4 divisors (see below), whose sum is σ = 16845154380. Its totient is φ = 16725684640.

The previous prime is 16785419507. The next prime is 16785419531. The reversal of 16785419509 is 90591458761.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90591458761 = 2087 ⋅43407503.

It can be written as a sum of positive squares in 2 ways, for example, as 7552131409 + 9233288100 = 86903^2 + 96090^2 .

It is a cyclic number.

It is not a de Polignac number, because 16785419509 - 2¹ = 16785419507 is a prime.

It is a super-4 number, since 4×16785419509⁴ (a number of 42 digits) contains 4444 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 16785419509.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16785419507) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29867014 + ... + 29867575.

It is an arithmetic number, because the mean of its divisors is an integer number (4211288595).

Almost surely, 2^16785419509 is an apocalyptic number.

It is an amenable number.

16785419509 is a deficient number, since it is larger than the sum of its proper divisors (59734871).

16785419509 is an equidigital number, since it uses as much as digits as its factorization.

16785419509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59734870.

The product of its (nonzero) digits is 2721600, while the sum is 55.

The spelling of 16785419509 in words is "sixteen billion, seven hundred eighty-five million, four hundred nineteen thousand, five hundred nine".