680565781 has 8 divisors (see below), whose sum is σ = 794338560. Its totient is φ = 570930288.

The previous prime is 680565763. The next prime is 680565793. The reversal of 680565781 is 187565086.

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 680565781 - 2⁹ = 680565269 is a prime.

It is a super-2 number, since 2×680565781² = 926339564536279922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (680565701) 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, 1033966 + ... + 1034623.

It is an arithmetic number, because the mean of its divisors is an integer number (99292320).

Almost surely, 2^680565781 is an apocalyptic number.

It is an amenable number.

680565781 is a deficient number, since it is larger than the sum of its proper divisors (113772779).

680565781 is a wasteful number, since it uses less digits than its factorization.

680565781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2068643.

The product of its (nonzero) digits is 403200, while the sum is 46.

The square root of 680565781 is about 26087.6557206660. The cubic root of 680565781 is about 879.6097533606.

It can be divided in two parts, 68056 and 5781, that added together give a palindrome (73837).

The spelling of 680565781 in words is "six hundred eighty million, five hundred sixty-five thousand, seven hundred eighty-one".