680655 has 8 divisors (see below), whose sum is σ = 1089072. Its totient is φ = 363008.

The previous prime is 680651. The next prime is 680657. The reversal of 680655 is 556086.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 680655 - 2² = 680651 is a prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 680655.

It is not an unprimeable number, because it can be changed into a prime (680651) 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 7 ways as a sum of consecutive naturals, for example, 22674 + ... + 22703.

It is an arithmetic number, because the mean of its divisors is an integer number (136134).

2⁶⁸⁰⁶⁵⁵ is an apocalyptic number.

680655 is a deficient number, since it is larger than the sum of its proper divisors (408417).

680655 is a wasteful number, since it uses less digits than its factorization.

680655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45385.

The product of its (nonzero) digits is 7200, while the sum is 30.

The square root of 680655 is about 825.0181816178. The cubic root of 680655 is about 87.9648189260.

Subtracting from 680655 its sum of digits (30), we obtain a square (680625 = 825²).

The spelling of 680655 in words is "six hundred eighty thousand, six hundred fifty-five".