1685001680 has 20 divisors (see below), whose sum is σ = 3917629092. Its totient is φ = 674000640.

The previous prime is 1685001677. The next prime is 1685001701. The reversal of 1685001680 is 861005861.

It can be written as a sum of positive squares in 2 ways, for example, as 1330206784 + 354794896 = 36472^2 + 18836^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a self number, because there is not a number n which added to its sum of digits gives 1685001680.

It is a congruent 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, 10531181 + ... + 10531340.

Almost surely, 2^1685001680 is an apocalyptic number.

1685001680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1685001680 is an abundant number, since it is smaller than the sum of its proper divisors (2232627412).

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

1685001680 is a wasteful number, since it uses less digits than its factorization.

1685001680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21062534 (or 21062528 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 35.

The square root of 1685001680 is about 41048.7719670150. The cubic root of 1685001680 is about 1189.9629675645.

The spelling of 1685001680 in words is "one billion, six hundred eighty-five million, one thousand, six hundred eighty".