680491009 has 16 divisors (see below), whose sum is σ = 758294784. Its totient is φ = 605404800.

The previous prime is 680490997. The next prime is 680491043. The reversal of 680491009 is 900194086.

It is not a de Polignac number, because 680491009 - 2⁹ = 680490497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (680497009) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 268669 + ... + 271189.

It is an arithmetic number, because the mean of its divisors is an integer number (47393424).

Almost surely, 2^680491009 is an apocalyptic number.

It is an amenable number.

680491009 is a deficient number, since it is larger than the sum of its proper divisors (77803775).

680491009 is a wasteful number, since it uses less digits than its factorization.

680491009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3048.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 680491009 is about 26086.2225897120. Note that the first 3 decimals coincide. The cubic root of 680491009 is about 879.5775386989.

The spelling of 680491009 in words is "six hundred eighty million, four hundred ninety-one thousand, nine".