681310979856 has 480 divisors, whose sum is σ = 2288151465600. Its totient is φ = 187280916480.

The previous prime is 681310979777. The next prime is 681310979857. The reversal of 681310979856 is 658979013186.

It is a junction number, because it is equal to n+sod(n) for n = 681310979793 and 681310979802.

It is not an unprimeable number, because it can be changed into a prime (681310979857) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 44345616 + ... + 44360976.

It is an arithmetic number, because the mean of its divisors is an integer number (4766982220).

Almost surely, 2^681310979856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 681310979856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1144075732800).

681310979856 is an abundant number, since it is smaller than the sum of its proper divisors (1606840485744).

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

681310979856 is a wasteful number, since it uses less digits than its factorization.

681310979856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15479 (or 15470 counting only the distinct ones).

The product of its (nonzero) digits is 19595520, while the sum is 63.

The spelling of 681310979856 in words is "six hundred eighty-one billion, three hundred ten million, nine hundred seventy-nine thousand, eight hundred fifty-six".