681291718261 has 8 divisors (see below), whose sum is σ = 849402661824. Its totient is φ = 530876663520.

The previous prime is 681291718249. The next prime is 681291718297. The reversal of 681291718261 is 162817192186.

681291718261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 681291718261 - 2⁵ = 681291718229 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 681291718199 and 681291718208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681291758261) 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, 4423972120 + ... + 4423972273.

It is an arithmetic number, because the mean of its divisors is an integer number (106175332728).

Almost surely, 2^681291718261 is an apocalyptic number.

It is an amenable number.

681291718261 is a deficient number, since it is larger than the sum of its proper divisors (168110943563).

681291718261 is a wasteful number, since it uses less digits than its factorization.

681291718261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8847944411.

The product of its digits is 580608, while the sum is 52.

The spelling of 681291718261 in words is "six hundred eighty-one billion, two hundred ninety-one million, seven hundred eighteen thousand, two hundred sixty-one".