1680813 has 6 divisors (see below), whose sum is σ = 2427854. Its totient is φ = 1120536.

The previous prime is 1680803. The next prime is 1680821. The reversal of 1680813 is 3180861.

It can be written as a sum of positive squares in only one way, i.e., 1432809 + 248004 = 1197^2 + 498^2 .

It is not a de Polignac number, because 1680813 - 2⁸ = 1680557 is a prime.

It is a Duffinian number.

It is a Curzon number.

1680813 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1680803) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 93370 + ... + 93387.

2^1680813 is an apocalyptic number.

It is an amenable number.

1680813 is a deficient number, since it is larger than the sum of its proper divisors (747041).

1680813 is a wasteful number, since it uses less digits than its factorization.

1680813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186763 (or 186760 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 1680813 is about 1296.4617233069. The cubic root of 1680813 is about 118.8976121872.

The spelling of 1680813 in words is "one million, six hundred eighty thousand, eight hundred thirteen".