1680897689 has 4 divisors (see below), whose sum is σ = 1681416720. Its totient is φ = 1680378660.

The previous prime is 1680897683. The next prime is 1680897697. The reversal of 1680897689 is 9867980861.

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 a de Polignac number, because none of the positive numbers 2^k-1680897689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1680897683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 254627 + ... + 261144.

It is an arithmetic number, because the mean of its divisors is an integer number (420354180).

Almost surely, 2^1680897689 is an apocalyptic number.

It is an amenable number.

1680897689 is a deficient number, since it is larger than the sum of its proper divisors (519031).

1680897689 is an equidigital number, since it uses as much as digits as its factorization.

1680897689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519030.

The product of its (nonzero) digits is 10450944, while the sum is 62.

The square root of 1680897689 is about 40998.7522858928. The cubic root of 1680897689 is about 1188.9960906821.

The spelling of 1680897689 in words is "one billion, six hundred eighty million, eight hundred ninety-seven thousand, six hundred eighty-nine".