1685407991760 has 120 divisors (see below), whose sum is σ = 5712090195240. Its totient is φ = 445318788096.

The previous prime is 1685407991747. The next prime is 1685407991767. The reversal of 1685407991760 is 671997045861.

1685407991760 is a `hidden beast` number, since 1 + 6 + 8 + 540 + 79 + 9 + 17 + 6 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 878838751296 + 806569240464 = 937464^2 + 898092^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1685407991767) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10659339 + ... + 10816298.

It is an arithmetic number, because the mean of its divisors is an integer number (47600751627).

Almost surely, 2^{1685407991760} is an apocalyptic number.

1685407991760 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1685407991760 is an abundant number, since it is smaller than the sum of its proper divisors (4026682203480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1685407991760 is a wasteful number, since it uses less digits than its factorization.

1685407991760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21475765 (or 21475756 counting only the distinct ones).

The product of its (nonzero) digits is 22861440, while the sum is 63.

The spelling of 1685407991760 in words is "one trillion, six hundred eighty-five billion, four hundred seven million, nine hundred ninety-one thousand, seven hundred sixty".