16680255785 has 4 divisors (see below), whose sum is σ = 20016306948. Its totient is φ = 13344204624.

The previous prime is 16680255769. The next prime is 16680255803. The reversal of 16680255785 is 58755208661.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4377674896 + 12302580889 = 66164^2 + 110917^2 .

It is a cyclic number.

It is not a de Polignac number, because 16680255785 - 2⁴ = 16680255769 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1668025574 + ... + 1668025583.

It is an arithmetic number, because the mean of its divisors is an integer number (5004076737).

Almost surely, 2^16680255785 is an apocalyptic number.

It is an amenable number.

16680255785 is a deficient number, since it is larger than the sum of its proper divisors (3336051163).

16680255785 is an equidigital number, since it uses as much as digits as its factorization.

16680255785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3336051162.

The product of its (nonzero) digits is 4032000, while the sum is 53.

The spelling of 16680255785 in words is "sixteen billion, six hundred eighty million, two hundred fifty-five thousand, seven hundred eighty-five".