680240857 has 4 divisors (see below), whose sum is σ = 680317876. Its totient is φ = 680163840.

The previous prime is 680240851. The next prime is 680240861. The reversal of 680240857 is 758042086.

680240857 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 333573696 + 346667161 = 18264^2 + 18619^2 .

It is a cyclic number.

It is not a de Polignac number, because 680240857 - 2¹¹ = 680238809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (680240851) 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, 23244 + ... + 43597.

It is an arithmetic number, because the mean of its divisors is an integer number (170079469).

Almost surely, 2^680240857 is an apocalyptic number.

It is an amenable number.

680240857 is a deficient number, since it is larger than the sum of its proper divisors (77019).

680240857 is a wasteful number, since it uses less digits than its factorization.

680240857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77018.

The product of its (nonzero) digits is 107520, while the sum is 40.

The square root of 680240857 is about 26081.4274340957. The cubic root of 680240857 is about 879.4697464115.

The spelling of 680240857 in words is "six hundred eighty million, two hundred forty thousand, eight hundred fifty-seven".