68640804044660 has 24 divisors (see below), whose sum is σ = 144179296901640. Its totient is φ = 27449920016384.

The previous prime is 68640804044623. The next prime is 68640804044723. The reversal of 68640804044660 is 6644040804686.

It can be written as a sum of positive squares in 4 ways, for example, as 14351641182736 + 54289162861924 = 3788356^2 + 7368118^2 .

It is a junction number, because it is equal to n+sod(n) for n = 68640804044596 and 68640804044605.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 400012169 + ... + 400183728.

It is an arithmetic number, because the mean of its divisors is an integer number (6007470704235).

Almost surely, 2^{68640804044660} is an apocalyptic number.

It is an amenable number.

68640804044660 is an abundant number, since it is smaller than the sum of its proper divisors (75538492856980).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

68640804044660 is a wasteful number, since it uses less digits than its factorization.

68640804044660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 800200195 (or 800200193 counting only the distinct ones).

The product of its (nonzero) digits is 21233664, while the sum is 56.

The spelling of 68640804044660 in words is "sixty-eight trillion, six hundred forty billion, eight hundred four million, forty-four thousand, six hundred sixty".