681699 has 4 divisors (see below), whose sum is σ = 908936. Its totient is φ = 454464.

The previous prime is 681689. The next prime is 681719. The reversal of 681699 is 996186.

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

It is not a de Polignac number, because 681699 - 2¹⁵ = 648931 is a prime.

It is a D-number.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 681699.

It is not an unprimeable number, because it can be changed into a prime (681689) 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, 113614 + ... + 113619.

It is an arithmetic number, because the mean of its divisors is an integer number (227234).

2⁶⁸¹⁶⁹⁹ is an apocalyptic number.

681699 is a deficient number, since it is larger than the sum of its proper divisors (227237).

681699 is a wasteful number, since it uses less digits than its factorization.

681699 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227236.

The product of its digits is 23328, while the sum is 39.

The square root of 681699 is about 825.6506525159. The cubic root of 681699 is about 88.0097699208.

The spelling of 681699 in words is "six hundred eighty-one thousand, six hundred ninety-nine".