1680349477 has 4 divisors (see below), whose sum is σ = 1680435820. Its totient is φ = 1680263136.

The previous prime is 1680349439. The next prime is 1680349501. The reversal of 1680349477 is 7749430861.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 7749430861 = 2557 ⋅3030673.

It can be written as a sum of positive squares in 2 ways, for example, as 1342929316 + 337420161 = 36646^2 + 18369^2 .

It is a cyclic number.

It is not a de Polignac number, because 1680349477 - 2¹¹ = 1680347429 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 1680349477.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1680349427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1273 + ... + 57985.

It is an arithmetic number, because the mean of its divisors is an integer number (420108955).

Almost surely, 2^1680349477 is an apocalyptic number.

It is an amenable number.

1680349477 is a deficient number, since it is larger than the sum of its proper divisors (86343).

1680349477 is an equidigital number, since it uses as much as digits as its factorization.

1680349477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86342.

The product of its (nonzero) digits is 1016064, while the sum is 49.

The square root of 1680349477 is about 40992.0660250249. The cubic root of 1680349477 is about 1188.8668159491.

The spelling of 1680349477 in words is "one billion, six hundred eighty million, three hundred forty-nine thousand, four hundred seventy-seven".