680345 has 4 divisors (see below), whose sum is σ = 816420. Its totient is φ = 544272.

The previous prime is 680341. The next prime is 680347. The reversal of 680345 is 543086.

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

It can be written as a sum of positive squares in 2 ways, for example, as 274576 + 405769 = 524^2 + 637^2 .

It is a cyclic number.

It is not a de Polignac number, because 680345 - 2² = 680341 is a prime.

It is not an unprimeable number, because it can be changed into a prime (680341) 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, 68030 + ... + 68039.

It is an arithmetic number, because the mean of its divisors is an integer number (204105).

2⁶⁸⁰³⁴⁵ is an apocalyptic number.

It is an amenable number.

680345 is a deficient number, since it is larger than the sum of its proper divisors (136075).

680345 is a wasteful number, since it uses less digits than its factorization.

680345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136074.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 680345 is about 824.8302855739. The cubic root of 680345 is about 87.9514625586.

The spelling of 680345 in words is "six hundred eighty thousand, three hundred forty-five".