681692377717 has 8 divisors (see below), whose sum is σ = 740626982424. Its totient is φ = 623685877248.

The previous prime is 681692377631. The next prime is 681692377747. The reversal of 681692377717 is 717773296186.

It can be written as a sum of positive squares in 4 ways, for example, as 13024743876 + 668667633841 = 114126^2 + 817721^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-681692377717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681692377747) 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, 232024528 + ... + 232027465.

It is an arithmetic number, because the mean of its divisors is an integer number (92578372803).

Almost surely, 2^681692377717 is an apocalyptic number.

It is an amenable number.

681692377717 is a deficient number, since it is larger than the sum of its proper divisors (58934604707).

681692377717 is a wasteful number, since it uses less digits than its factorization.

681692377717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 464052119.

The product of its digits is 37340352, while the sum is 64.

The spelling of 681692377717 in words is "six hundred eighty-one billion, six hundred ninety-two million, three hundred seventy-seven thousand, seven hundred seventeen".