1685722371905 has 16 divisors (see below), whose sum is σ = 2376514897344. Its totient is φ = 1131673759680.

The previous prime is 1685722371889. The next prime is 1685722371929. The reversal of 1685722371905 is 5091732275861.

It is not a de Polignac number, because 1685722371905 - 2⁴ = 1685722371889 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1178826119 + ... + 1178827548.

It is an arithmetic number, because the mean of its divisors is an integer number (148532181084).

Almost surely, 2^{1685722371905} is an apocalyptic number.

It is an amenable number.

1685722371905 is a deficient number, since it is larger than the sum of its proper divisors (690792525439).

1685722371905 is a wasteful number, since it uses less digits than its factorization.

1685722371905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2357653696.

The product of its (nonzero) digits is 6350400, while the sum is 56.

The spelling of 1685722371905 in words is "one trillion, six hundred eighty-five billion, seven hundred twenty-two million, three hundred seventy-one thousand, nine hundred five".