681813907 has 4 divisors (see below), whose sum is σ = 703807936. Its totient is φ = 659819880.

The previous prime is 681813901. The next prime is 681813931. The reversal of 681813907 is 709318186.

681813907 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 681813907 - 2¹¹ = 681811859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681813901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10996968 + ... + 10997029.

It is an arithmetic number, because the mean of its divisors is an integer number (175951984).

Almost surely, 2^681813907 is an apocalyptic number.

681813907 is a deficient number, since it is larger than the sum of its proper divisors (21994029).

681813907 is a wasteful number, since it uses less digits than its factorization.

681813907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21994028.

The product of its (nonzero) digits is 72576, while the sum is 43.

The square root of 681813907 is about 26111.5665366902. The cubic root of 681813907 is about 880.1471461069.

The spelling of 681813907 in words is "six hundred eighty-one million, eight hundred thirteen thousand, nine hundred seven".