1680688637 has 4 divisors (see below), whose sum is σ = 1753762080. Its totient is φ = 1607615196.

The previous prime is 1680688631. The next prime is 1680688673. The reversal of 1680688637 is 7368860861.

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.

It is a cyclic number.

It is not a de Polignac number, because 1680688637 - 2¹⁶ = 1680623101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1680688631) 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, 36536687 + ... + 36536732.

It is an arithmetic number, because the mean of its divisors is an integer number (438440520).

Almost surely, 2^1680688637 is an apocalyptic number.

It is an amenable number.

1680688637 is a deficient number, since it is larger than the sum of its proper divisors (73073443).

1680688637 is an equidigital number, since it uses as much as digits as its factorization.

1680688637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73073442.

The product of its (nonzero) digits is 2322432, while the sum is 53.

The square root of 1680688637 is about 40996.2027143978. The cubic root of 1680688637 is about 1188.9467971176.

The spelling of 1680688637 in words is "one billion, six hundred eighty million, six hundred eighty-eight thousand, six hundred thirty-seven".