1685882385909 has 10 divisors (see below), whose sum is σ = 2518416897590. Its totient is φ = 1123921590552.

The previous prime is 1685882385899. The next prime is 1685882385917. The reversal of 1685882385909 is 9095832885861.

1685882385909 is a `hidden beast` number, since 1 + 6 + 8 + 5 + 8 + 8 + 23 + 8 + 590 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1172434184100 + 513448201809 = 1082790^2 + 716553^2 .

It is not a de Polignac number, because 1685882385909 - 2¹⁶ = 1685882320373 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1685882385949) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 10406681314 + ... + 10406681475.

It is an arithmetic number, because the mean of its divisors is an integer number (251841689759).

Almost surely, 2^{1685882385909} is an apocalyptic number.

It is an amenable number.

1685882385909 is a deficient number, since it is larger than the sum of its proper divisors (832534511681).

1685882385909 is an equidigital number, since it uses as much as digits as its factorization.

1685882385909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20813362801 (or 20813362792 counting only the distinct ones).

The product of its (nonzero) digits is 298598400, while the sum is 72.

The spelling of 1685882385909 in words is "one trillion, six hundred eighty-five billion, eight hundred eighty-two million, three hundred eighty-five thousand, nine hundred nine".