680612168521 has 8 divisors (see below), whose sum is σ = 725908386600. Its totient is φ = 635900418048.

The previous prime is 680612168503. The next prime is 680612168563. The reversal of 680612168521 is 125861216086.

It can be written as a sum of positive squares in 4 ways, for example, as 247641588496 + 432970580025 = 497636^2 + 658005^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 680612168521 - 2⁹ = 680612168009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (680612168221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 146114496 + ... + 146119153.

It is an arithmetic number, because the mean of its divisors is an integer number (90738548325).

Almost surely, 2^680612168521 is an apocalyptic number.

It is an amenable number.

680612168521 is a deficient number, since it is larger than the sum of its proper divisors (45296218079).

680612168521 is a wasteful number, since it uses less digits than its factorization.

680612168521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292233803.

The product of its (nonzero) digits is 276480, while the sum is 46.

The spelling of 680612168521 in words is "six hundred eighty billion, six hundred twelve million, one hundred sixty-eight thousand, five hundred twenty-one".