680821821778 has 32 divisors (see below), whose sum is σ = 1229905612800. Its totient is φ = 276119032464.

The previous prime is 680821821737. The next prime is 680821821793. The reversal of 680821821778 is 877128128086.

It is a super-2 number, since 2×680821821778² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1169698 + ... + 1652221.

It is an arithmetic number, because the mean of its divisors is an integer number (38434550400).

Almost surely, 2^680821821778 is an apocalyptic number.

680821821778 is a deficient number, since it is larger than the sum of its proper divisors (549083791022).

680821821778 is a wasteful number, since it uses less digits than its factorization.

680821821778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2822854.

The product of its (nonzero) digits is 4816896, while the sum is 58.

The spelling of 680821821778 in words is "six hundred eighty billion, eight hundred twenty-one million, eight hundred twenty-one thousand, seven hundred seventy-eight".