1680832821 has 4 divisors (see below), whose sum is σ = 2241110432. Its totient is φ = 1120555212.

The previous prime is 1680832799. The next prime is 1680832859. The reversal of 1680832821 is 1282380861.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1282380861 = 3 ⋅427460287.

It is not a de Polignac number, because 1680832821 - 2⁷ = 1680832693 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1680832821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1680832871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 280138801 + ... + 280138806.

It is an arithmetic number, because the mean of its divisors is an integer number (560277608).

Almost surely, 2^1680832821 is an apocalyptic number.

It is an amenable number.

1680832821 is a deficient number, since it is larger than the sum of its proper divisors (560277611).

1680832821 is an equidigital number, since it uses as much as digits as its factorization.

1680832821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560277610.

The product of its (nonzero) digits is 36864, while the sum is 39.

The square root of 1680832821 is about 40997.9611810148. The cubic root of 1680832821 is about 1188.9807955234.

The spelling of 1680832821 in words is "one billion, six hundred eighty million, eight hundred thirty-two thousand, eight hundred twenty-one".