680549 has 4 divisors (see below), whose sum is σ = 682560. Its totient is φ = 678540.

The previous prime is 680539. The next prime is 680567. The reversal of 680549 is 945086.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 945086 = 2 ⋅472543.

It is a cyclic number.

It is not a de Polignac number, because 680549 - 2⁸ = 680293 is a prime.

It is a Duffinian number.

It is a Curzon number.

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 680549.

It is not an unprimeable number, because it can be changed into a prime (680509) 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, 359 + ... + 1220.

It is an arithmetic number, because the mean of its divisors is an integer number (170640).

2⁶⁸⁰⁵⁴⁹ is an apocalyptic number.

It is an amenable number.

680549 is a deficient number, since it is larger than the sum of its proper divisors (2011).

680549 is a wasteful number, since it uses less digits than its factorization.

680549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2010.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 680549 is about 824.9539381081. The cubic root of 680549 is about 87.9602523664.

The spelling of 680549 in words is "six hundred eighty thousand, five hundred forty-nine".