680723681 has 4 divisors (see below), whose sum is σ = 742607664. Its totient is φ = 618839700.

The previous prime is 680723657. The next prime is 680723731. The reversal of 680723681 is 186327086.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 680723681 - 2¹⁰ = 680722657 is a prime.

It is a super-2 number, since 2×680723681² = 926769459748379522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (680723611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30941975 + ... + 30941996.

It is an arithmetic number, because the mean of its divisors is an integer number (185651916).

Almost surely, 2^680723681 is an apocalyptic number.

It is an amenable number.

680723681 is a deficient number, since it is larger than the sum of its proper divisors (61883983).

680723681 is a wasteful number, since it uses less digits than its factorization.

680723681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61883982.

The product of its (nonzero) digits is 96768, while the sum is 41.

The square root of 680723681 is about 26090.6818807022. The cubic root of 680723681 is about 879.6777750194.

The spelling of 680723681 in words is "six hundred eighty million, seven hundred twenty-three thousand, six hundred eighty-one".