681747907 has 4 divisors (see below), whose sum is σ = 682678720. Its totient is φ = 680817096.

The previous prime is 681747887. The next prime is 681747917. The reversal of 681747907 is 709747186.

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 681747907 - 2¹⁹ = 681223619 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681747917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 464307 + ... + 465772.

It is an arithmetic number, because the mean of its divisors is an integer number (170669680).

Almost surely, 2^681747907 is an apocalyptic number.

681747907 is a deficient number, since it is larger than the sum of its proper divisors (930813).

681747907 is an equidigital number, since it uses as much as digits as its factorization.

681747907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 930812.

The product of its (nonzero) digits is 592704, while the sum is 49.

The square root of 681747907 is about 26110.3026983603. The cubic root of 681747907 is about 880.1187455979.

The spelling of 681747907 in words is "six hundred eighty-one million, seven hundred forty-seven thousand, nine hundred seven".