680906 has 4 divisors (see below), whose sum is σ = 1021362. Its totient is φ = 340452.

The previous prime is 680881. The next prime is 680917. The reversal of 680906 is 609086.

680906 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 625681 + 55225 = 791^2 + 235^2 .

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 680906.

It is an unprimeable number.

680906 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 170225 + ... + 170228.

2⁶⁸⁰⁹⁰⁶ is an apocalyptic number.

680906 is a deficient number, since it is larger than the sum of its proper divisors (340456).

680906 is a wasteful number, since it uses less digits than its factorization.

680906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340455.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 680906 is about 825.1702854563. The cubic root of 680906 is about 87.9756303043.

The spelling of 680906 in words is "six hundred eighty thousand, nine hundred six".