680705 has 8 divisors (see below), whose sum is σ = 825000. Its totient is φ = 539136.

The previous prime is 680681. The next prime is 680707. The reversal of 680705 is 507086.

It can be written as a sum of positive squares in 4 ways, for example, as 92416 + 588289 = 304^2 + 767^2 .

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 680705 - 2¹⁰ = 679681 is a prime.

It is an Ulam number.

It is a plaindrome in base 9 and base 13.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 680705.

It is not an unprimeable number, because it can be changed into a prime (680707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80 + ... + 1169.

It is an arithmetic number, because the mean of its divisors is an integer number (103125).

2⁶⁸⁰⁷⁰⁵ is an apocalyptic number.

It is an amenable number.

680705 is a deficient number, since it is larger than the sum of its proper divisors (144295).

680705 is a wasteful number, since it uses less digits than its factorization.

680705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1363.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 680705 is about 825.0484834239. The cubic root of 680705 is about 87.9669727990.

The spelling of 680705 in words is "six hundred eighty thousand, seven hundred five".